This commit removes the autocompletion feature for HTML entities.
HTML entites are things like `&`, `<` etc.
There are a few reasons for the decision:
1. It is outside the core functionality of Angular LS
2. The implementation relies on regex, which incurs performance cost
3. There isn't much value if users do not already know which entity
they want to use
4. The list that we provide is not exhaustive
PR Close#37515
cc552dd702