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-arrow-left.svg

@@ -1 +1 @@
-<svg viewBox="0 0 10 16" class="svg octicon-arrow-left" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M6 3L0 8l6 5v-3h4V6H6V3z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-arrow-left" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M7.78 12.53a.75.75 0 01-1.06 0L2.47 8.28a.75.75 0 010-1.06l4.25-4.25a.75.75 0 011.06 1.06L4.81 7h7.44a.75.75 0 010 1.5H4.81l2.97 2.97a.75.75 0 010 1.06z"/></svg>