chore: update GH Action templates to use gapic-libraries-bom version (#12872)

This PR updates the templates in
`sdk-platform-java/hermetic_build/library_generation/owlbot/templates/java_library/`
to use `gapic-libraries-bom` and the `v{version}` tag format for action
versioning.

The Git tag for shared dependencies BOM version is created by an
automation (GitHub Actions) automatically. While it would work just
fine, chaining automated events will make future troubleshooting
difficult. So let's rely on the original tag of the google-cloud-java
repository, which matches gapic-libraries-bom version.

b/503444342

Author: suztomo

sdk-platform-java/hermetic_build/library_generation/owlbot/templates/java_library/.github/scripts/update_generation_config.sh

@@ -150,10 +150,10 @@ update_config "gapic_generator_version" "${latest_gapic_generator_version}" "${g
 # Update the GitHub Actions reference to the latest.
 # After the google-cloud-java monorepo migration of sdk-platform-java,
 # we cannot rely on the gapic-generator-java version tag. Let's use
-# the shared dependencies BOM version
-latest_shared_dependencies_bom_version=$(get_latest_released_version "com.google.cloud" "google-cloud-shared-dependencies")
+# the gapic-libraries-bom version
+latest_gapic_libraries_bom_version=$(get_latest_released_version "com.google.cloud" "gapic-libraries-bom")
 update_action "googleapis/google-cloud-java/sdk-platform-java/.github/scripts" \
-  "google-cloud-shared-dependencies/v${latest_shared_dependencies_bom_version}" \
+  "v${latest_gapic_libraries_bom_version}" \
   "${workflow}"
 
 # Update libraries-bom version to the latest

sdk-platform-java/hermetic_build/library_generation/owlbot/templates/java_library/renovate.json

@@ -29,9 +29,9 @@
         "^.github/workflows/unmanaged_dependency_check.yaml$"
       ],
       "matchStrings": [
-        "uses: googleapis/google-cloud-java/sdk-platform-java/java-shared-dependencies/unmanaged-dependency-check@google-cloud-shared-dependencies/v(?<currentValue>.+?)\\n"
+        "uses: googleapis/google-cloud-java/sdk-platform-java/java-shared-dependencies/unmanaged-dependency-check@v(?<currentValue>.+?)\\n"
       ],
-      "depNameTemplate": "com.google.cloud:google-cloud-shared-dependencies",
+      "depNameTemplate": "com.google.cloud:gapic-libraries-bom",
       "datasourceTemplate": "maven"
     }
   ],