Include git-hook regeneration in restore documentation (#8181)

* Added admin cmd ref to backup-restore guide

* Clarified reason for command execution

* Include directive for where command should be executed from

Co-Authored-By: guillep2k <18600385+guillep2k@users.noreply.github.com>

* Be direct in consequences

Co-Authored-By: guillep2k <18600385+guillep2k@users.noreply.github.com>

docs/content/doc/usage/backup-and-restore.en-us.md

@@ -79,3 +79,9 @@ mysql -u$USER -p$PASS $DATABASE <gitea-db.sql
 # or  sqlite3 $DATABASE_PATH <gitea-db.sql
 service gitea restart
 ```
+
+Repository git-hooks should be regenerated if installation method is changed (eg. binary -> Docker), or if Gitea is installed to a different directory than the previous installation.
+
+With Gitea running, and from the directory Gitea's binary is located, execute: `./gitea admin regenerate hooks`
+
+This ensures that application and configuration file paths in repository git-hooks are consistent and applicable to the current installation. If these paths are not updated, repository `push` actions will fail.