Replace CI with the main branch (#722)

- Add 2.21 stages (Sanity, Docker, Remote)
- Update distro versions (Fedora 44, RHEL 10.1/9.7, FreeBSD 14.4/15.0)
- Remove CentOS 7 from Docker 2.16
- Add 2.21 to Summary stage dependencies
- Backport #718

tests/unit/requirements.txt

@@ -1,42 +0,0 @@
-boto3
-placebo
-pycrypto
-passlib
-pypsrp
-python-memcached
-pytz
-pyvmomi
-redis
-requests
-setuptools > 0.6 # pytest-xdist installed via requirements does not work with very old setuptools (sanity_ok)
-unittest2 ; python_version < '2.7'
-importlib ; python_version < '2.7'
-netaddr
-ipaddress
-netapp-lib
-solidfire-sdk-python
-
-# requirements for F5 specific modules
-f5-sdk ; python_version >= '2.7'
-f5-icontrol-rest ; python_version >= '2.7'
-deepdiff
-
-# requirement for Fortinet specific modules
-pyFMG
-
-# requirement for aci_rest module
-xmljson
-
-# requirement for winrm connection plugin tests
-pexpect
-
-# requirement for the linode module
-linode-python # APIv3
-linode_api4 ; python_version > '2.6' # APIv4
-
-# requirement for the gitlab module
-python-gitlab
-httmock
-
-# requirment for kubevirt modules
-openshift ; python_version >= '2.7'