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-stopwatch.svg

@@ -1 +1 @@
-<svg viewBox="0 0 16 16" class="svg octicon-stopwatch" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M5.75.75A.75.75 0 016.5 0h3a.75.75 0 010 1.5h-.75v1l-.001.041a6.718 6.718 0 013.464 1.435l.007-.006.75-.75a.75.75 0 111.06 1.06l-.75.75-.006.007a6.75 6.75 0 11-10.548 0L2.72 5.03l-.75-.75a.75.75 0 011.06-1.06l.75.75.007.006A6.718 6.718 0 017.25 2.541a.756.756 0 010-.041v-1H6.5a.75.75 0 01-.75-.75zM8 14.5A5.25 5.25 0 108 4a5.25 5.25 0 000 10.5zm.389-6.7l1.33-1.33a.75.75 0 111.061 1.06L9.45 8.861A1.502 1.502 0 018 10.75a1.5 1.5 0 11.389-2.95z"/></svg>
+<svg viewBox="0 0 16 16" class="svg octicon-stopwatch" width="16" height="16" aria-hidden="true"><path fill-rule="evenodd" d="M5.75.75A.75.75 0 0 1 6.5 0h3a.75.75 0 0 1 0 1.5h-.75v1l-.001.041a6.718 6.718 0 0 1 3.464 1.435l.007-.006.75-.75a.75.75 0 1 1 1.06 1.06l-.75.75-.006.007a6.75 6.75 0 1 1-10.548 0L2.72 5.03l-.75-.75a.75.75 0 0 1 1.06-1.06l.75.75.007.006A6.718 6.718 0 0 1 7.25 2.541a.756.756 0 0 1 0-.041v-1H6.5a.75.75 0 0 1-.75-.75zM8 14.5A5.25 5.25 0 1 0 8 4a5.25 5.25 0 0 0 0 10.5zm.389-6.7 1.33-1.33a.75.75 0 1 1 1.061 1.06L9.45 8.861A1.502 1.502 0 0 1 8 10.75a1.5 1.5 0 1 1 .389-2.95z"/></svg>