By default force vertical tabs on mobile (#19486)

* By default force vertical tabs on mobile

- While experimenting with using vertical tabs instead of horizontal
tabs on gitea for a better mobile experience, I made a recent
PR(https://github.com/go-gitea/gitea/pull/19468) in order to see if
there was any objections to this new behavior for the repo headers(one
of the most annoying horizontal tabs). This PR had no objections and
even a user commenting that this change is brilliant.
- This PR now improves upon the previous PR by making this the de-facto
behavior for all menu's on mobile. The only exemption is the navbar
which also uses the menu but caught some layout errors with the changes.

* Fix organisation

* Fix repo/wiki buttons

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

templates/base/head.tmpl

@@ -85,7 +85,7 @@
 		{{template "custom/body_inner_pre" .}}
 
 		{{if not .PageIsInstall}}
-			<div class="ui top secondary stackable main menu following bar light">
+			<div class="ui top secondary stackable main menu following bar light no-vertical-tabs">
 				{{template "base/head_navbar" .}}
 			</div><!-- end bar -->
 		{{end}}