Exclude new GRPC example from BCR presubmit (#1192)

Signed-off-by: Brentley Jones <github@brentleyjones.com>

Author: brentleyjones

.bcr/presubmit.yml

@@ -26,6 +26,7 @@ tasks:
     - "@rules_swift//examples/xplatform/..."
     - "-@rules_swift//examples/xplatform/deprecated_grpc/..." # TODO: Fix grpc on Linux
     - "-@rules_swift//examples/xplatform/grpc/..." # TODO: Fix grpc on Linux
+    - "-@rules_swift//examples/xplatform/proto_library_group/..." # TODO: Fix grpc on Linux
   verify_targets_macos:
     name: Verify build targets
     bazel: ${{ bazel }}