Fix serviceworker output file and misc improvements (#11562) (#11610)

* Fix serviceworker output file and misc improvements

- Fix output file location for production build
- Cache more asset types: fonts and worker variants
- Parallelize a few tasks during initalization
- Only invalidate caches starting with our prefix
- Remove public/serviceworker.js before building
- Remove font preloads, they cause strange cors issues
- Misc eslint config adjustments

* remove webpack output files on watch-frontend

templates/base/head.tmpl

@@ -92,8 +92,6 @@
 	<link rel="mask-icon" href="{{StaticUrlPrefix}}/img/gitea-safari.svg" color="#609926">
 	<link rel="fluid-icon" href="{{StaticUrlPrefix}}/img/gitea-lg.png" title="{{AppName}}">
 	<link rel="stylesheet" href="{{StaticUrlPrefix}}/vendor/assets/font-awesome/css/font-awesome.min.css">
-	<link rel="preload" as="font" href="{{StaticUrlPrefix}}/fomantic/themes/default/assets/fonts/icons.woff2" type="font/woff2" crossorigin="anonymous">
-	<link rel="preload" as="font" href="{{StaticUrlPrefix}}/fomantic/themes/default/assets/fonts/outline-icons.woff2" type="font/woff2" crossorigin="anonymous">
 {{if .RequireSimpleMDE}}
 	<link rel="stylesheet" href="{{StaticUrlPrefix}}/vendor/plugins/simplemde/simplemde.min.css">
 {{end}}