fix: not able to update local created non-urlencoded wiki pages (#16139)

fix: not able to update local created non-urlencoded wiki pages (#16139)

* fix: not able to update local created non-urlencoded wiki pages

* tidy code

* as per suggestion

Signed-off-by: Andrew Thornton <art27@cantab.net>
* Don't replace space to dash for unescaped wiki filename

Co-authored-by: zeripath <art27@cantab.net>
* Remove incorrect comment

* Remove NameToUnescapedFilename()

Co-authored-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>