Add type changes for recent async_mysql changes made

Summary: I missed adding these in D88923858

Differential Revision: D90041756

fbshipit-source-id: e6c9b29aa95bce5b884c2a301a9dd4b685b0da13

Author: aditya-jalan

hphp/hack/hhi/stdlib/builtins_async_mysql.hhi

@@ -268,6 +268,9 @@ namespace {
     public function recvGtid(): string {}
     public function responseAttributes(): Map<string, string> {}
     public function resultSizeBytes(): int {}
+    public function mysqlInfo(): ?string {}
+    public function rowsMatched(): ?int {}
+    public function warningsCount(): int {}
   }
   class AsyncMysqlRowBlock
     implements Countable, KeyedTraversable<int, AsyncMysqlRow> {