Update Octicons to v10 (#12240)

* Update Octicons to v10

Besides a few renames, these icons are no longer present in v10 that we've
used, so had to change:

file-symlink-directory -> file-submodule
internal-repo -> repo
repo-force-push -> repo-push
repo-template-private -> repo-template

Fixes: https://github.com/go-gitea/gitea/issues/11889
Ref: https://github.com/primer/octicons/releases/tag/v10.0.0

* add custom sliders svg for removed octicon-settings

* apply suggestion

* fix triangles and use play on admin dashboard

* add custom mirror svg

* add missing build files

* unify custom svgs

* move to octicon-repo-clone to gitea-mirror

* use octicon-x on conflicts

* tweak timeline icons

* tweak comment buttons

* update settings icon to octicons v1

* switch to octicon-mirror and octicon-tools

* replace two wiki buttons with octicons

* remove whitespace in svg sources

* Fix filepath basename on Windows for SVG bindata (#12241)

* move octicons to devDependencies

* move back to dependencies

* move svgo to devDependencies again

Co-authored-by: Cirno the Strongest <1447794+CirnoT@users.noreply.github.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

public/img/svg/octicon-horizontal-rule.svg

@@ -1 +1 @@
-<svg viewBox="0 0 10 16" class="svg octicon-horizontal-rule" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M1 7h2v2h1V3H3v3H1V3H0v6h1V7zm9 2V7H9v2h1zm0-3V4H9v2h1zM7 6V4h2V3H6v6h1V7h2V6H7zm-7 7h10v-2H0v2z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-horizontal-rule" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M0 7.75A.75.75 0 01.75 7h14.5a.75.75 0 010 1.5H.75A.75.75 0 010 7.75z"/></svg>