* Update JS dependencies

- Update all JS dependencies minus vue and vue-loader
- Adapt to jest 28
- Add new eslint rules
- Tested Mermaid and Swagger-UI

* switch to @happy-dom/jest-environment for faster tests

* bump eslint env to es2022

* Add copy button to markdown code blocks

Done mostly in JS because I think it's better not to try getting buttons
past the markup sanitizer.

* add svg module tests

* fix sanitizer regexp

* remove outdated comment

* vertically center button in issue comments as well

* add comment to css

* fix undefined on view file line copy

* combine animation less files

* Update modules/markup/markdown/markdown.go

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

* add test for different sizes

* add cloneNode and add tests for it

* use deep clone

* remove useless optional chaining

* remove the svg node cache

* unify clipboard copy string and i18n

* remove unused var

* remove unused localization

* minor css tweaks to the button

* comment tweak

* remove useless attribute

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

* Update JS dependencies

- Upgrade to eslint 8 and add new plugin rules
- Adapt to various API changes
- Rebuild SVGs

* fix webpack warning on license

* order options alphabetically

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

* Update JS dependencies

- Update all JS dependencies
- Adapt to recent webpack changes
- Add new lint rules and fix issues
- Regenerate SVGs and update svgo api usage

Fixes: https://github.com/go-gitea/gitea/pull/16492

* adapt jest config and sort keys

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

- Define jest rootDir to limit where it looks for test files
- Add missing dependency on test-frontend target so it can be ran from a
  clean checkout

- Add basic frontend unit testing infrastructure using jest in ESM mode
- Rename 'make test' to 'make test-backend'
- Introduce 'make test-frontend' and 'make test' that runs both
- Bump Node.js requirement to v12. v10 will be EOL in less than a month.
- Convert all build-related JS files to ESM.

I opted to run frontend tests run as part of the compliance pipeline because
they complete fast and are not platform-specific like the golang tests.