cleanup locale function usage (#27227) (#27240)

Backport #27227 by @denyskon

Throughout the Gitea codebase, you can meet some weird constructions to
make `locale.Tr` work in subtemplates.
Since we now have `ctx.Locale.Tr` which solves that problem, clean up
various templates which pass `locale` through `dict` or use some weird
constructions like `$.root.locale`

Going on, it would be great to replace every case of `$.locale.Tr` and
`.locale.Tr` with `ctx.Locale.Tr`, but that needs to be done with
patience.

Co-authored-by: Denys Konovalov <kontakt@denyskon.de>

templates/user/settings/applications.tmpl

@@ -109,7 +109,7 @@
 	<div class="content">
 		<p>{{.locale.Tr "settings.access_token_deletion_desc"}}</p>
 	</div>
-	{{template "base/modal_actions_confirm" (dict "locale" $.locale "ModalButtonColors" "yellow")}}
+	{{template "base/modal_actions_confirm" (dict "ModalButtonColors" "yellow")}}
 </div>
 
 {{template "user/settings/layout_footer" .}}