Move jquery-minicolors to npm/webpack (#12305)

* Move jquery-minicolors to npm/webpack

- Unvendor and add as npm dependency
- Removed unneeded backend variable
- Fixed existing bug where picker would previously initizalize to the
  same green color when editing a label.

There was probably a version bump because the previous version was
over 3 years old but it seems to be compatible.

* use file-loader

* trailing comma and comment update

* misc tweaks

Co-authored-by: Lauris BH <lauris@nix.lv>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

.gitignore

@@ -79,6 +79,7 @@ coverage.all
 /public/serviceworker.js
 /public/css
 /public/fonts
+/public/img/webpack
 /web_src/fomantic/build
 /VERSION
 /.air