…monitor (getsentry#8032)

### Description

This fixes the flaky
`tests/test_monitor.py::test_segment_uses_downsampled_rate` (`assert
0.25 == 0.5`,
[job](https://github.com/getsentry/sentry-python/actions/runs/38393542918/job/115282966684)).
Its siblings `test_transaction_uses_downsampled_rate` and
`test_monitor_unhealthy` have the same race.

**Root cause**
These tests call `monitor.run()` by hand and assert exact
`downsample_factor` values. They also set `monitor.interval = 0.1`. The
first `monitor.is_healthy()` starts the monitor's background thread,
which then calls `run()` every 0.1 s as well. On a slow runner (the
failure was in Gevent 3.10, where the test took about 0.34 s), the
thread runs an extra unhealthy check before the sampling decision. The
factor goes from 1 to 2, so the sample rate is 0.25.

**Fix**
These tests now call `monitor.kill()` instead of shortening the
interval. The thread `is_healthy()` starts then exits right away, so
only the test's own `run()` calls change the factor. The assertions are
unchanged, and there are no retries, sleeps or skips. SDK code is
unchanged; this was a test bug.

**Reproduction:** getsentry/repro#62 (sentry-sdk
2.72.0, Python 3.12). With random gaps of 0–0.2 s before sampling, the
rate was wrong in 55 of 100 iterations. With gaps under 0.1 s it was 0
of 100, and with the background thread stopped it was 0 of 100.

**Original tests, local runs** (`py3.14-common`). Each run covered the 3
affected tests. A test-only `-p` plugin added a random wait before
`start_transaction` / `traces.start_span` to imitate a slow runner; no
test or SDK code was changed by it.
- `master`, no wait: 10 of 10 runs passed. The race doesn't show up
locally on its own.
- `master`, 0–200 ms wait: **11 of 15 runs failed**.
`test_segment_uses_downsampled_rate` failed 6 times and
`test_transaction_uses_downsampled_rate` 8 times.
- This branch, 0–200 ms wait: **40 of 40 runs passed**. The baseline
per-test failure rate was about 40%, so 9 clean runs would already give
99% confidence.
- This branch, 0–500 ms wait: **20 of 20 runs passed**.
- Regression checks: `tests/test_monitor.py`,
`tests/tracing/test_sampling.py` and `tests/tracing/test_decorator.py`
all passed (109 tests). `ruff` is clean. I haven't run the full common
suite or the gevent setup locally; CI covers those.

**Not changed here:** `test_trace_decorator_no_trx` also failed once,
with leftover monitor logs (`downsampling with a factor of 10`). The
likely cause is in `tests/conftest.py::sentry_init`: `inner()` assigns
`client` without `nonlocal`, so the `client.close()` in teardown never
runs. Monitor threads from earlier tests (with the 0.1 s interval) then
keep running. I'll handle that separately, because closing every test
client affects the whole suite.

#### Issues
* resolves: getsentry#8031

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/setup-java](https://redirect.github.com/actions/setup-java)
([changelog](https://redirect.github.com/actions/setup-java/compare/de7274f081f381c8f8158605e0321c36c376e2e6..b843ebf9b913146b38da2eaa7aeddf76074ae1ad))
| | digest | `de7274f` → `b843ebf` |
| [actions/setup-java](https://redirect.github.com/actions/setup-java)
([changelog](https://redirect.github.com/actions/setup-java/compare/de7274f081f381c8f8158605e0321c36c376e2e6..b843ebf9b913146b38da2eaa7aeddf76074ae1ad))
| action | digest | `de7274f` → `b843ebf` |
|
[getsentry/coverage-action](https://redirect.github.com/getsentry/coverage-action)
| | patch | `0.4.3` → `0.4.4` |
|
[getsentry/coverage-action](https://redirect.github.com/getsentry/coverage-action)
| action | patch | `0.4.3` → `0.4.4` |
| [java-jdk](https://adoptium.net) | uses-with | major | `21` → `25` |

---

### Release Notes

<details>
<summary>getsentry/coverage-action</summary>

###
[`v0.4.4`](https://redirect.github.com/getsentry/coverage-action/blob/HEAD/CHANGELOG.md#044)

[Compare
Source](https://redirect.github.com/getsentry/coverage-action/compare/0.4.3...0.4.4)

##### New Features ✨

- (status) Add status-key input to namespace commit statuses by
[@&#8203;tyrantkhan](https://redirect.github.com/tyrantkhan) in
[#&#8203;118](https://redirect.github.com/getsentry/coverage-action/pull/118)

##### Internal Changes 🔧

- (dashboard) Freeze the artifact fixture clock by
[@&#8203;MathurAditya724](https://redirect.github.com/MathurAditya724)
in
[#&#8203;120](https://redirect.github.com/getsentry/coverage-action/pull/120)
- (release) Default the merge target to main by
[@&#8203;MathurAditya724](https://redirect.github.com/MathurAditya724)
in
[#&#8203;121](https://redirect.github.com/getsentry/coverage-action/pull/121)
- (status) Document and verify independent package statuses by
[@&#8203;MathurAditya724](https://redirect.github.com/MathurAditya724)
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[#&#8203;119](https://redirect.github.com/getsentry/coverage-action/pull/119)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [getsentry/craft](https://redirect.github.com/getsentry/craft) |
action | minor | `2.34.1` → `2.35.0` |
| [getsentry/craft](https://redirect.github.com/getsentry/craft)
([changelog](https://redirect.github.com/getsentry/craft/compare/3f2abdc5703191d12ef2cc013f792f1bd220f44d..7a7857552e2cdc08b502de96e6076849c01fba32))
| workflow | digest | `3f2abdc` → `7a78575` |
| [java-jdk](https://adoptium.net) | uses-with | major | `21` → `25` |

---

### Release Notes

<details>
<summary>getsentry/craft</summary>

###
[`v2.35.0`](https://redirect.github.com/getsentry/craft/blob/HEAD/CHANGELOG.md#2350)

[Compare
Source](https://redirect.github.com/getsentry/craft/compare/2.34.1...2.35.0)

##### New Features ✨

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[@&#8203;MathurAditya724](https://redirect.github.com/MathurAditya724)
in [#&#8203;904](https://redirect.github.com/getsentry/craft/pull/904)

##### Bug Fixes 🐛

- (nuget) Pass --timeout to dotnet nuget push by
[@&#8203;sentry-junior](https://redirect.github.com/sentry-junior) in
[#&#8203;901](https://redirect.github.com/getsentry/craft/pull/901)

##### Internal Changes 🔧

- Add standalone Fossilize binaries and native smoke tests by
[@&#8203;MathurAditya724](https://redirect.github.com/MathurAditya724)
in [#&#8203;903](https://redirect.github.com/getsentry/craft/pull/903)

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