Cirrus: Add support for Ubuntu 20.x

Previously automation always dropped the minor version number for
distributions.  This was intended for presentation and conditional
simplicity. Bash does not support non-integer comparison natively.

With the release of version 20.10, supporting testing with it and
the LTS release (20.04) requires scripts to consider minor version
numbers for Ubuntu VMs.  This is necessary because many times in
the past, some behaviors needed to be conditional on the release
version number.

With this commit, the images and embedded scripts/tooling uses an
altered format of `$UBUNTU_NAME', `$PRIOR_UBUNTU_NAME`, and (crucially)
`$OS_RELEASE_VER` and `$OS_REL_VER`.  Any `.` characters appearing
in the official version (from `/etc/os-release`) are dropped, and
the result is concatenated.

For example the current Ubuntu LTS version is `20.04`.  Prior to
this commit, `$OS_RELEASE_VER` would have been `20`.  With this
change, `$OS_RELEASE_VER` will now show `2004`.  Similarly `20.10`
is shown as `2010`.

Signed-off-by: Chris Evich <cevich@redhat.com>

contrib/cirrus/runner.sh

@@ -41,7 +41,7 @@ function _run_automation() {
     req_env_vars CI DEST_BRANCH IMAGE_SUFFIX TEST_FLAVOR TEST_ENVIRON \
                  PODBIN_NAME PRIV_NAME DISTRO_NV CONTAINER USER HOME \
                  UID AUTOMATION_LIB_PATH SCRIPT_BASE OS_RELEASE_ID \
-                 OS_RELEASE_VER CG_FS_TYPE
+                 CG_FS_TYPE
     bigto ooe.sh dnf install -y ShellCheck  # small/quick addition
     $SCRIPT_BASE/shellcheck.sh
 }
@@ -64,12 +64,6 @@ function _run_unit() {
 }
 
 function _run_apiv2() {
-    # TODO Remove once VM's with dependency
-    if [[ "$OS_RELEASE_ID" == "fedora" ]]; then
-        dnf install -y python3-docker
-    else
-        apt-get -qq -y install python3-docker
-    fi
     make localapiv2 |& logformatter
 }