Add Troubleshooting guide for Local Setup

[sundaram2021]

Feature Description

There is a problem occurs while setting up the gitea repo locally after forking it

Screenshots

No response

[sundaram2021]

Created a PR for this.
Checkout it here

[wxiaoguang]

It is a git problem but not Gitea's problem, not related to Gitea.

#32194 (comment)