Update JS dependencies (#15033)

* Update JS dependencies

- Update all JS dependencies
- For octicons, rename trashcan to trash
- For svgo, migrate to v2 api, output seems to have slightly changed but icons look the same
- For stylelint, update config, fix custom property duplicates
- For monaco, drop legacy Edge support
- For eslint, enable new rules, fix new issues
- For less-loader, remove deprecated import syntax

* update svgo usage in generate-images and rebuild logo.svg with it

public/img/svg/octicon-screen-normal.svg

@@ -1 +1 @@
-<svg viewBox="0 0 16 16" class="svg octicon-screen-normal" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M5.25 1a.75.75 0 01.75.75v2.5A1.75 1.75 0 014.25 6h-2.5a.75.75 0 010-1.5h2.5a.25.25 0 00.25-.25v-2.5A.75.75 0 015.25 1zm5.5 0a.75.75 0 01.75.75v2.5c0 .138.112.25.25.25h2.5a.75.75 0 010 1.5h-2.5A1.75 1.75 0 0110 4.25v-2.5a.75.75 0 01.75-.75zM1 10.75a.75.75 0 01.75-.75h2.5c.966 0 1.75.784 1.75 1.75v2.5a.75.75 0 01-1.5 0v-2.5a.25.25 0 00-.25-.25h-2.5a.75.75 0 01-.75-.75zm9 1c0-.966.784-1.75 1.75-1.75h2.5a.75.75 0 010 1.5h-2.5a.25.25 0 00-.25.25v2.5a.75.75 0 01-1.5 0v-2.5z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-screen-normal" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M5.25 1a.75.75 0 0 1 .75.75v2.5A1.75 1.75 0 0 1 4.25 6h-2.5a.75.75 0 0 1 0-1.5h2.5a.25.25 0 0 0 .25-.25v-2.5A.75.75 0 0 1 5.25 1zm5.5 0a.75.75 0 0 1 .75.75v2.5c0 .138.112.25.25.25h2.5a.75.75 0 0 1 0 1.5h-2.5A1.75 1.75 0 0 1 10 4.25v-2.5a.75.75 0 0 1 .75-.75zM1 10.75a.75.75 0 0 1 .75-.75h2.5c.966 0 1.75.784 1.75 1.75v2.5a.75.75 0 0 1-1.5 0v-2.5a.25.25 0 0 0-.25-.25h-2.5a.75.75 0 0 1-.75-.75zm9 1c0-.966.784-1.75 1.75-1.75h2.5a.75.75 0 0 1 0 1.5h-2.5a.25.25 0 0 0-.25.25v2.5a.75.75 0 0 1-1.5 0v-2.5z"/></svg>