fix: 修复createSelectorQuery exec()不写回调函数时在支付宝小程序报错

src/platforms/mp-alipay/runtime/api/index.js

@@ -41,7 +41,9 @@ function createExecCallback (execCallback) {
         callback(res[index])
       })
     })
-    execCallback(res)
+    if (isFn(execCallback)) {
+      execCallback(res)
+    }
   }
 }