Update module google.golang.org/grpc to v1.76.0

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

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

@@ -332,6 +332,11 @@ type AuthorityOverrider interface {
 	// OverrideAuthority returns the authority to use for a ClientConn with the
 	// given target. The implementation must generate it without blocking,
 	// typically in line, and must keep it unchanged.
+	//
+	// The returned string must be a valid ":authority" header value, i.e. be
+	// encoded according to
+	// [RFC3986](https://datatracker.ietf.org/doc/html/rfc3986#section-3.2) as
+	// necessary.
 	OverrideAuthority(Target) string
 }