Update google.golang.org/grpc from v1.27.1 to v1.38.0

v1.38.0 is used by Kubernetes since
https://github.com/kubernetes/kubernetes/pull/100488.

Signed-off-by: Kazuyoshi Kato <katokazu@amazon.com>

vendor/google.golang.org/protobuf/runtime/protoimpl/impl.go

@@ -0,0 +1,44 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package protoimpl contains the default implementation for messages
+// generated by protoc-gen-go.
+//
+// WARNING: This package should only ever be imported by generated messages.
+// The compatibility agreement covers nothing except for functionality needed
+// to keep existing generated messages operational. Breakages that occur due
+// to unauthorized usages of this package are not the author's responsibility.
+package protoimpl
+
+import (
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/internal/filetype"
+	"google.golang.org/protobuf/internal/impl"
+)
+
+// UnsafeEnabled specifies whether package unsafe can be used.
+const UnsafeEnabled = impl.UnsafeEnabled
+
+type (
+	// Types used by generated code in init functions.
+	DescBuilder = filedesc.Builder
+	TypeBuilder = filetype.Builder
+
+	// Types used by generated code to implement EnumType, MessageType, and ExtensionType.
+	EnumInfo      = impl.EnumInfo
+	MessageInfo   = impl.MessageInfo
+	ExtensionInfo = impl.ExtensionInfo
+
+	// Types embedded in generated messages.
+	MessageState     = impl.MessageState
+	SizeCache        = impl.SizeCache
+	WeakFields       = impl.WeakFields
+	UnknownFields    = impl.UnknownFields
+	ExtensionFields  = impl.ExtensionFields
+	ExtensionFieldV1 = impl.ExtensionField
+
+	Pointer = impl.Pointer
+)
+
+var X impl.Export