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-cross-reference.svg

@@ -0,0 +1 @@
+<svg viewBox="0 0 16 16" class="svg octicon-cross-reference" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M16 1.25v4.146a.25.25 0 01-.427.177L14.03 4.03l-3.75 3.75a.75.75 0 11-1.06-1.06l3.75-3.75-1.543-1.543A.25.25 0 0111.604 1h4.146a.25.25 0 01.25.25zM2.75 3.5a.25.25 0 00-.25.25v7.5c0 .138.112.25.25.25h2a.75.75 0 01.75.75v2.19l2.72-2.72a.75.75 0 01.53-.22h4.5a.25.25 0 00.25-.25v-2.5a.75.75 0 111.5 0v2.5A1.75 1.75 0 0113.25 13H9.06l-2.573 2.573A1.457 1.457 0 014 14.543V13H2.75A1.75 1.75 0 011 11.25v-7.5C1 2.784 1.784 2 2.75 2h5.5a.75.75 0 010 1.5h-5.5z"/></svg>