[CI] Remove openstack-tox-functional-py36-fips

The job definition does not exist anymore and zuul config reports error
because of this, so let's get rid of this from the check queue (gate
queue does not even have it).

Change-Id: I0b211b7c8fcfebeaf9f1bc9bbee0c6527faa53d9

Author: Elod Illes

.zuul.yaml

@@ -306,7 +306,6 @@
       - release-notes-jobs-python3
     check:
       jobs:
-        - openstack-tox-functional-py36-fips
         - openstack-tox-functional-py39
         - glance-tox-functional-py39-rbac-defaults
         - glance-ceph-thin-provisioning: