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

templates/repo/issue/view_content/pull.tmpl

@@ -73,7 +73,7 @@
 
 								{{if .CanChange }}
 									<a href="#" class="ui poping up icon re-request-review {{if .Checked}}checked{{end}}" data-issue-id="{{$.Issue.ID}}" data-content="{{if .Checked}} {{$.i18n.Tr "repo.issues.remove_request_review"}} {{else}} {{$.i18n.Tr "repo.issues.re_request_review"}} {{end}}"  data-id="{{.ItemID}}" data-update-url="{{$.RepoLink}}/issues/request_review">
-										{{if .Checked}} {{svg "octicon-trashcan"}} {{else}} {{svg "octicon-sync"}} {{end}}
+										{{if .Checked}} {{svg "octicon-trash"}} {{else}} {{svg "octicon-sync"}} {{end}}
 									</a>
 								{{end}}
 								{{svg (printf "octicon-%s" .Review.Type.Icon)}}