Running clean repository command trashes .idea

[okonet]

Describe the bug

When running "Clean repository" task via yarn bootstrap, it says that .idea will be preserved along with .vscode but in reality is removes .idea as well.

To Reproduce

1. Run yarn bootstrap command
2. Choose Clean repository in the list of tasks
3. Press y when asked

The log will contain the following

trashed .yarn/install-state.gz
trashed examples/react-ts-webpack4/
trashed reset.log
trashed .idea/

[shilman]

@okonet --reset deletes any files that git doesn't know about, so the fix is probably just to update the docs

[okonet]

I think that the intent is correct since it makes WebStorm users suffer for now specific reason. I already have a fix in place so I'll PR soon.