remove hls.js from the repository and restore plain MIT license (#3008)

.github/workflows/bump_hls_js.yml

@@ -20,8 +20,9 @@ jobs:
         && ((git checkout deps/hlsjs && git rebase ${GITHUB_REF_NAME}) || git checkout -b deps/hlsjs)
 
     - run: >
-        curl -o internal/servers/hls/hls.min.js https://cdn.jsdelivr.net/npm/hls.js@latest/dist/hls.min.js
-        && echo VERSION=$(cat internal/servers/hls/hls.min.js | grep -o '"version",get:function(){return".*"}' | sed 's/"version",get:function(){return"\(.*\)"}/\1/') >> $GITHUB_ENV
+        VERSION=$(curl -s https://api.github.com/repos/video-dev/hls.js/releases?per_page=1 | grep tag_name | sed 's/\s\+"tag_name": "\(.\+\)",/\1/')
+        && echo $VERSION > internal/servers/hls/hlsjsdownloader/VERSION
+        && echo VERSION=$VERSION >> $GITHUB_ENV
 
     - id: check_repo
       run: >