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/github.com/emicklei/go-restful/v3/extensions.go

@@ -0,0 +1,21 @@
+package restful
+
+// Copyright 2021 Ernest Micklei. All rights reserved.
+// Use of this source code is governed by a license
+// that can be found in the LICENSE file.
+
+// ExtensionProperties provides storage of vendor extensions for entities
+type ExtensionProperties struct {
+	// Extensions vendor extensions used to describe extra functionality
+	// (https://swagger.io/docs/specification/2-0/swagger-extensions/)
+	Extensions map[string]interface{}
+}
+
+// AddExtension adds or updates a key=value pair to the extension map.
+func (ep *ExtensionProperties) AddExtension(key string, value interface{}) {
+	if ep.Extensions == nil {
+		ep.Extensions = map[string]interface{}{key: value}
+	} else {
+		ep.Extensions[key] = value
+	}
+}