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-heart-fill.svg

@@ -1 +1 @@
-<svg viewBox="0 0 16 16" class="svg octicon-heart-fill" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M7.655 14.916L8 14.25l.345.666a.752.752 0 01-.69 0zm0 0L8 14.25l.345.666.002-.001.006-.003.018-.01a7.643 7.643 0 00.31-.17 22.08 22.08 0 003.433-2.414C13.956 10.731 16 8.35 16 5.5 16 2.836 13.914 1 11.75 1 10.203 1 8.847 1.802 8 3.02 7.153 1.802 5.797 1 4.25 1 2.086 1 0 2.836 0 5.5c0 2.85 2.045 5.231 3.885 6.818a22.075 22.075 0 003.744 2.584l.018.01.006.003h.002z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-heart-fill" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M7.655 14.916 8 14.25l.345.666a.752.752 0 0 1-.69 0zm0 0L8 14.25l.345.666.002-.001.006-.003.018-.01a7.643 7.643 0 0 0 .31-.17 22.08 22.08 0 0 0 3.433-2.414C13.956 10.731 16 8.35 16 5.5 16 2.836 13.914 1 11.75 1 10.203 1 8.847 1.802 8 3.02 7.153 1.802 5.797 1 4.25 1 2.086 1 0 2.836 0 5.5c0 2.85 2.045 5.231 3.885 6.818a22.075 22.075 0 0 0 3.744 2.584l.018.01.006.003h.002z"/></svg>