Configure Docker build for Bazel 7.7.0 and add gRPC xDS upb map itertion compatibility patches

[vkarampudi]

Description

Following the repository upgrade to Bazel 7.7.0 (.bazelversion), the standalone Docker gRPC server build (build_docker_image.sh) encountered resolution and compilation failures. This PR addresses both the Java runtime bootstrap under Bazel 7 and fixes transitive upb map iteration signature mismatches in gRPC.

Changes

• Dockerfile (ml_metadata/tools/docker_server/Dockerfile):
  • Updated BAZEL_VERSION to 7.7.0.
  • Installed openjdk-11-jdk-headless in the builder stage to satisfy Bazel 7's @local_jdk requirement inside the container.
• WORKSPACE:
  • Added compatibility stubs via patch_cmds in com_github_grpc_grpc to patch out unused xDS client map iteration (xds_metadata_parser.cc, xds_http_rbac_filter.cc, xds_route_config_parser.cc) that conflicts with modern upb signatures.

Verification

• Verified C++ server target compiles and links successfully (//ml_metadata/metadata_store:metadata_store_server).
• Verified clean end-to-end Docker image build (docker build --no-cache).

[rwitcher]

LGTM