Stop trimming preceding and suffixing spaces from editor filenames (#18334)

* Stop trimming preceding and suffixing spaces from editor filenames

In #5702 it was decided to trim preceding and suffixed spaces aswell as / from
editing file filenames. This was because at this point in time the url-safety of
Gitea was much poorer.

We can now drop this requirement and file editing should work correctly.

Fix #18176

Signed-off-by: Andrew Thornton <art27@cantab.net>

CHANGELOG.md

@@ -228,6 +228,7 @@ been added to each release, please refer to the [blog](https://blog.gitea.io).
   * Add left padding for chunk header of split diff view (#13397)
   * Allow U2F 2FA without TOTP (#11573)
 * BUGFIXES
+  * Stop trimming preceding and suffixing spaces from editor filenames (#18334)
   * Restore propagation of ErrDependenciesLeft (#18325)
   * Fix PR comments UI (#18323)
   * Use indirect comparison when showing pull requests (#18313)