Fix incorrect cache_memory reset in functionsLibCtxClear (valkey-io#1255

)

functionsLibCtxClear should clear the provided lib_ctx parameter,
not the static variable curr_functions_lib_ctx, as this contradicts
the function's intended purpose.

The impact i guess is minor, like in some unhappy paths (diskless load
fails, function restore fails?), we will mess up the functions_caches
field, which is used in used_memory_functions / used_memory_scripts
fileds in INFO.

Signed-off-by: Binbin <[email protected]>

src/functions.c

@@ -175,7 +175,7 @@ void functionsLibCtxClear(functionsLibCtx *lib_ctx) {
         stats->n_lib = 0;
     }
     dictReleaseIterator(iter);
-    curr_functions_lib_ctx->cache_memory = 0;
+    lib_ctx->cache_memory = 0;
 }
 
 void functionsLibCtxClearCurrent(int async) {