similar to https://github.com/frappe/frappe/pull/14061
This will ensure that only one instance of the following tests run per
PR and cancel previous running/queued jobs when new commits are pushed.
- Server / unit tests
- UI tests
- Patch test
* chore: remove deprecated and empty QUnit tests
* ci: fix UI test config
Testing library was added on Frappe, in order to reuse command testing
library has to be installed during setup process.