chore: Update gapic-generator-python to v1.18.0

Google APIs · copybara-github · commit 6330f0389afd · 2024-05-30T07:49:25.000-07:00
PiperOrigin-RevId: 638650618
diff --git a/WORKSPACE b/WORKSPACE
@@ -312,7 +312,7 @@ load("@rules_gapic//python:py_gapic_repositories.bzl", "py_gapic_repositories")
 
 py_gapic_repositories()
 
-_gapic_generator_python_version = "1.17.1"
+_gapic_generator_python_version = "1.18.0"
 
 http_archive(
     name = "gapic_generator_python",
