Exclude Google Cloud Storage gRPC packages (#7988)

## What changed?

Stripped Google Cloud Storage's gRPC dependencies out for builds via the
Makefile.

## Why?

Reduce binary size by 16MB; and reduces build times a little (ie
linking).

**Before**

```
-rwxr-xr-x@ 1 stephan  staff   119M Jun 30 11:23 temporal-server
```

**After**

```
-rwxr-xr-x@ 1 stephan  staff   103M Jun 30 11:24 temporal-server
```

## How did you test it?
- [x] built
- [ ] run locally and tested manually
- [ ] covered by existing tests
- [x] added new unit test(s)
- [ ] added new functional test(s)

## Potential risks

Yes, since there are no end-to-end tests, if anyone started using
`storage.NewGRPCClient` that would fail silently. I added a (crude) test
to catch that.

Author: stephanos

Makefile

@@ -44,7 +44,10 @@ PERSISTENCE_DRIVER ?= cassandra
 TEMPORAL_DB ?= temporal
 VISIBILITY_DB ?= temporal_visibility
 
-ALL_BUILD_TAGS := $(BUILD_TAG),
+# The `disable_grpc_modules` build tag excludes gRPC dependencies from cloud.google.com/go/storage,
+# reducing binary size by 16MB since we only use the REST client (storage.NewClient), not the
+# gRPC client (storage.NewGRPCClient). Related issue: https://github.com/googleapis/google-cloud-go/issues/12343
+ALL_BUILD_TAGS := disable_grpc_modules,$(BUILD_TAG)
 ALL_TEST_TAGS := $(ALL_BUILD_TAGS),test_dep,$(TEST_TAG)
 BUILD_TAG_FLAG := -tags $(ALL_BUILD_TAGS)
 TEST_TAG_FLAG := -tags $(ALL_TEST_TAGS)

common/archiver/gcloud/connector/client_delegate.go

@@ -86,7 +86,6 @@ func newDefaultClientDelegate(ctx context.Context) (*clientDelegate, error) {
 }
 
 func newClientDelegateWithCredentials(ctx context.Context, credentialsPath string) (*clientDelegate, error) {
-
 	jsonKey, err := os.ReadFile(credentialsPath)
 	if err != nil {
 		return newDefaultClientDelegate(ctx)

common/archiver/gcloud/connector/client_test.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"io"
 	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 
@@ -243,7 +244,6 @@ func (s *clientSuite) TestQuery() {
 }
 
 func (s *clientSuite) TestQueryWithFilter() {
-
 	ctx := context.Background()
 	mockBucketHandleClient := connector.NewMockBucketHandleWrapper(s.controller)
 	mockStorageClient := connector.NewMockGcloudStorageClient(s.controller)
@@ -303,3 +303,32 @@ func newWorkflowIDPrecondition(workflowID string) connector.Precondition {
 		return false
 	}
 }
+
+// Ensures that no code in this package or its parent folder accidentally uses gRPC functions
+// since they are stripped from the binary via `disable_grpc_modules`. This is crude but effective.
+func (s *clientSuite) TestNoGRPCUsage() {
+	currentPackageFiles, err := filepath.Glob("*.go")
+	s.NoError(err)
+	parentPackageFiles, err := filepath.Glob("../*.go")
+	s.NoError(err)
+	allFiles := append(currentPackageFiles, parentPackageFiles...)
+
+	var checkedClientFile bool
+	for _, file := range allFiles {
+		if strings.HasSuffix(file, "_test.go") {
+			continue
+		}
+
+		content, err := os.ReadFile(file)
+		s.NoError(err)
+
+		if strings.Contains(string(content), "NewGRPCClient") {
+			s.T().Errorf("❌ Found forbidden gRPC usage in file: %s", file)
+		}
+
+		// Check for client.go in both current and parent directories
+		checkedClientFile = checkedClientFile || strings.HasSuffix(file, "client.go")
+	}
+
+	s.True(checkedClientFile, "should have checked client.go for gRPC usage")
+}