[release/v1.20.x] Prepare release 1.20.2 (open-telemetry#7264)

Prepare release 1.20.2.

[release/v1.20.x] Prepare release 1.20.1 (open-telemetry#7242)

Prepare release 1.20.1.

[release/v1.20.x] Prepare release 1.20.0 (open-telemetry#7208)

Prepare release 1.20.0.

[release/v1.19.x] Prepare release 1.19.2 (open-telemetry#7024)

Prepare release 1.19.2.

[release/v1.19.x] Fix website PR (open-telemetry#6923)

Clean cherry-pick of open-telemetry#6869 to the `release/v1.19.x` branch.

Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>

[release/v1.19.x] Prepare release 1.19.0 (open-telemetry#6860)

Prepare release 1.19.0.

Fix examples in release branch (open-telemetry#6625)

Prepare release 1.17.0 (open-telemetry#6487)

Prepare release 1.16.0 (open-telemetry#6342)

Prepare release 1.15.0 (open-telemetry#6181)