chore: use gapic-generator-python 1.2.0

Google APIs · copybara-github · commit e6e875a456c0 · 2022-08-12T13:56:19.000-07:00
PiperOrigin-RevId: 467286830
diff --git a/WORKSPACE b/WORKSPACE
@@ -278,7 +278,7 @@ load("@rules_python//python:pip.bzl", "pip_install")
 
 pip_install()
 
-_gapic_generator_python_version = "1.1.2"
+_gapic_generator_python_version = "1.2.0"
 
 http_archive(
     name = "gapic_generator_python",
