improve generic list and namespacedlist

- allow empty apiGroup
- select rest api path based on apiGroup value

Author: DanyT

kubernetes/src/generic.c

@@ -95,7 +95,7 @@ char* Generic_readResource(genericClient_t *client, const char *name) {
 
 char *Generic_listNamespaced(genericClient_t *client, const char *namespace) {
     char path[128];
-    if (client->apiGroup) {
+    if (client->apiGroup && strlen(client->apiGroup)) {
         snprintf(path, 128, "/apis/%s/%s/namespaces/%s/%s",
                  client->apiGroup, client->apiVersion, namespace, client->resourcePlural);
     } else {
@@ -107,7 +107,7 @@ char *Generic_listNamespaced(genericClient_t *client, const char *namespace) {
 
 char *Generic_list(genericClient_t *client) {
     char path[128];
-    if (client->apiGroup) {
+    if (client->apiGroup && strlen(client->apiGroup)) {
         snprintf(path, 128, "/apis/%s/%s/%s",
                  client->apiGroup, client->apiVersion, client->resourcePlural);
     } else {