Milestone statistics not being recalculated on issue delete

[stuzer05]

Description

When you delete issues from milestone, milestone's "completed" and "# closed issues" field not being recalculated.

To replicate this issue:

1. create a milestone
2. create any number of issues
3. close any number of issues
4. delete closed issue
5. Milestone's statistics will be broken

Gitea Version

1.18.0+dev-450-g10228387d

Can you reproduce the bug on the Gitea demo site?

Yes

Log Gist

No response

Screenshots

Git Version

No response

Operating System

No response

How are you running Gitea?

gitea's demo site

Database

No response