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-hubot.svg

@@ -1 +1 @@
-<svg viewBox="0 0 16 16" class="svg octicon-hubot" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M0 8a8 8 0 1116 0v5.25a.75.75 0 01-1.5 0V8a6.5 6.5 0 10-13 0v5.25a.75.75 0 01-1.5 0V8zm5.5 4.25a.75.75 0 01.75-.75h3.5a.75.75 0 010 1.5h-3.5a.75.75 0 01-.75-.75zM3 6.75C3 5.784 3.784 5 4.75 5h6.5c.966 0 1.75.784 1.75 1.75v1.5A1.75 1.75 0 0111.25 10h-6.5A1.75 1.75 0 013 8.25v-1.5zm1.47-.53a.75.75 0 011.06 0l.97.97.97-.97a.75.75 0 011.06 0l.97.97.97-.97a.75.75 0 111.06 1.06l-1.5 1.5a.75.75 0 01-1.06 0L8 7.81l-.97.97a.75.75 0 01-1.06 0l-1.5-1.5a.75.75 0 010-1.06z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-hubot" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M0 8a8 8 0 1 1 16 0v5.25a.75.75 0 0 1-1.5 0V8a6.5 6.5 0 1 0-13 0v5.25a.75.75 0 0 1-1.5 0V8zm5.5 4.25a.75.75 0 0 1 .75-.75h3.5a.75.75 0 0 1 0 1.5h-3.5a.75.75 0 0 1-.75-.75zM3 6.75C3 5.784 3.784 5 4.75 5h6.5c.966 0 1.75.784 1.75 1.75v1.5A1.75 1.75 0 0 1 11.25 10h-6.5A1.75 1.75 0 0 1 3 8.25v-1.5zm1.47-.53a.75.75 0 0 1 1.06 0l.97.97.97-.97a.75.75 0 0 1 1.06 0l.97.97.97-.97a.75.75 0 1 1 1.06 1.06l-1.5 1.5a.75.75 0 0 1-1.06 0L8 7.81l-.97.97a.75.75 0 0 1-1.06 0l-1.5-1.5a.75.75 0 0 1 0-1.06z"/></svg>