✨ add runAfterFirstMounted effect hook

[kuitos]

Checklist

• documentation is changed or added
• commit message follows commit guidelines

Description of change

add runAfterFirstMounted effect hook, usually used for add tracking code.

import { runAfterFirstMounted } from 'qiankun';

recordStart();
runAfterFirstMounted(() => recordEnd());

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This change is 

[howel52]

为何 startGoogleAnalysis 要放在 first app mount 后？