Exercise multiple ansible versions in CI (#8172)

* Ansible: separate requirements files for supported ansible versions

* Ansible: allow using ansible 2.11

* CI: Exercise Ansible 2.9 and Ansible 2.11 in a basic AIO CI job

* CI: Allow running a reset test outside of idempotency tests and running it in stage1

* CI: move ubuntu18-calico-aio job to stage2 and relay only on ubuntu20 with the variously supported ansible versions for stage1

* CI: add capability to install collections or roles from ansible-galaxy to mitigate missing behavior in older ansible versions