rebase: Bump google.golang.org/grpc from 1.64.0 to 1.65.0

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.64.0 to 1.65.0.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](https://github.com/grpc/grpc-go/compare/v1.64.0...v1.65.0)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/google.golang.org/grpc/metadata/metadata.go

@@ -90,21 +90,6 @@ func Pairs(kv ...string) MD {
 	return md
 }
 
-// String implements the Stringer interface for pretty-printing a MD.
-// Ordering of the values is non-deterministic as it ranges over a map.
-func (md MD) String() string {
-	var sb strings.Builder
-	fmt.Fprintf(&sb, "MD{")
-	for k, v := range md {
-		if sb.Len() > 3 {
-			fmt.Fprintf(&sb, ", ")
-		}
-		fmt.Fprintf(&sb, "%s=[%s]", k, strings.Join(v, ", "))
-	}
-	fmt.Fprintf(&sb, "}")
-	return sb.String()
-}
-
 // Len returns the number of items in md.
 func (md MD) Len() int {
 	return len(md)