deps: update dependency com.google.cloud:sdk-platform-java-config to v3.28.1 (#2467)

Author: renovate-bot

.github/workflows/unmanaged_dependency_check.yaml

@@ -17,6 +17,6 @@ jobs:
  # repository
  .kokoro/build.sh
  - name: Unmanaged dependency check
- uses: googleapis/sdk-platform-java/java-shared-dependencies/unmanaged-dependency-check@google-cloud-shared-dependencies/v3.27.0
+ uses: googleapis/sdk-platform-java/java-shared-dependencies/unmanaged-dependency-check@google-cloud-shared-dependencies/v3.28.1
  with:
  bom-path: google-cloud-storage-bom/pom.xml