Modules: Invalidate saved_oparray after use (#7688)

We wanna avoid a chance of someone using the pointer in it after it'll be freed / realloced.

src/module.c

@@ -609,6 +609,8 @@ void moduleHandlePropagationAfterCommandCallback(RedisModuleCtx *ctx) {
         redisOpArrayFree(&server.also_propagate);
         /* Restore the previous oparray in case of nexted use of the API. */
         server.also_propagate = ctx->saved_oparray;
+        /* We're done with saved_oparray, let's invalidate it. */
+        redisOpArrayInit(&ctx->saved_oparray);
     }
 }