1. Re-generate c client to merge PR #7467 of openapi-generator

2. Remove the duplicated definition of "clear_and_free_string_list" after code merge

kubernetes/include/apiClient.h

@@ -23,6 +23,7 @@ typedef struct apiClient_t {
     sslConfig_t *sslConfig;
     void *dataReceived;
     long dataReceivedLen;
+    void (*data_callback_func)(void **, long *);
     long response_code;
     list_t *apiKeys_BearerToken;
 } apiClient_t;