build: move e2e dependencies into e2e/go.mod

Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>

e2e/vendor/google.golang.org/protobuf/internal/descopts/options.go

@@ -0,0 +1,29 @@
+// Copyright 2019 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 descopts contains the nil pointers to concrete descriptor options.
+//
+// This package exists as a form of reverse dependency injection so that certain
+// packages (e.g., internal/filedesc and internal/filetype can avoid a direct
+// dependency on the descriptor proto package).
+package descopts
+
+import "google.golang.org/protobuf/reflect/protoreflect"
+
+// These variables are set by the init function in descriptor.pb.go via logic
+// in internal/filetype. In other words, so long as the descriptor proto package
+// is linked in, these variables will be populated.
+//
+// Each variable is populated with a nil pointer to the options struct.
+var (
+	File           protoreflect.ProtoMessage
+	Enum           protoreflect.ProtoMessage
+	EnumValue      protoreflect.ProtoMessage
+	Message        protoreflect.ProtoMessage
+	Field          protoreflect.ProtoMessage
+	Oneof          protoreflect.ProtoMessage
+	ExtensionRange protoreflect.ProtoMessage
+	Service        protoreflect.ProtoMessage
+	Method         protoreflect.ProtoMessage
+)