Improved code by updating any interfaces

Change-Id: I9a2e630c37f3c427569f5bbd773978c2705dc08c
diff --git a/auth/oauth_test.go b/auth/oauth_test.go
index 9c6b0cc..65b4e50 100644
--- a/auth/oauth_test.go
+++ b/auth/oauth_test.go
@@ -126,7 +126,7 @@
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path == "/token" {
 			w.Header().Set("Content-Type", "application/json")
-			response := map[string]interface{}{
+			response := map[string]any{
 				"access_token": "test-access-token",
 				"token_type":   "Bearer",
 				"expires_in":   3600,
@@ -162,7 +162,7 @@
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path == "/token" {
 			w.Header().Set("Content-Type", "application/json")
-			response := map[string]interface{}{
+			response := map[string]any{
 				"access_token": "client-credentials-token",
 				"token_type":   "Bearer",
 				"expires_in":   3600,
@@ -249,7 +249,7 @@
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path == "/token" {
 			w.Header().Set("Content-Type", "application/json")
-			response := map[string]interface{}{
+			response := map[string]any{
 				"access_token":  "refreshed-access-token",
 				"refresh_token": "new-refresh-token",
 				"token_type":    "Bearer",