fix a couple of memory leaks

Author: ekoby

library/external_auth.c

@@ -167,6 +167,7 @@ extern int ziti_ext_auth_token(ziti_context ztx, const char *token) {
     NEWP(jwt, zt_jwt);
     if (zt_jwt_parse(token, jwt) != 0) {
         ZTX_LOG(WARN, "failed to parse JWT token");
+        free(jwt);
         return ZITI_JWT_INVALID;
     }
     ZTX_LOG(DEBUG, "received access token: %s", json_object_get_string(jwt->claims));

library/utils.c

@@ -778,11 +778,9 @@ cstr jwt_issuer(const char *jwt) {
     assert(jwt);
     json_object *claims = json_tokener_parse(jwt_payload(jwt));
     json_object *iss = json_object_object_get(claims, "iss");
-    if (iss) {
-        return cstr_from(json_object_get_string(iss));
-    }
-
-    return cstr_lit("<unknown>");
+    cstr result = iss ? cstr_from(json_object_get_string(iss)) : cstr_lit("<unknown>");
+    json_object_put(claims);
+    return result;
 }
 
 const char *jwt_payload(const char *jwt) {