Use Ana06/get-changed-files@v1.2 which removes the _head commit is ahead
of the base commit_ check. This made the action failed in not up-to-date
branches (in which rebasing is needed).
It supersedes https://github.com/fireeye/capa/pull/599
Ana06/get-changed-files@v1.1 is a fork of
https://github.com/jitterbit/get-changed-files, which supports
`pull_request_target` and allow to filter files using regular
expressions.
As we need to use `pull_request_target`, Ana06/get-changed-files@v1.1
works, but jitterbit/get-changed-files@v1 doesn't.