CI: Fix molecule job failure

The molecule job is failing with this error in rich/_lru_cache.py:

    ImportError: cannot import name 'OrderedDict' from 'typing_extensions'

This followed the release of rich 12.1.0 [1]. Cap rich below this
version.

This commit also separates molecule requirements into their own file.
This is similar to I4cad83c92c32d1db2a5d3c03a78a1c533a8b9633 applied on
the master branch during the Xena cycle, although we keep using upper
constraints for molecule because they work.

It also includes changes from 07eb067:
pin ansible-lint to <6 and ignore changes to molecule-requirements.txt
for jobs that don't use it.

[1] Textualize/rich#2164

Change-Id: I555702c19acd1cb4c4aa52987cd7991334ae1cd7

molecule-requirements.txt

@@ -0,0 +1,12 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
+ansible-lint>=3.0.0,<6.0.0,!=4.3.0 # MIT
+docker # Apache-2.0
+molecule # MIT
+molecule-docker # MIT
+pytest-molecule # MIT
+pytest-testinfra
+rich<12.1.0
+yamllint # GPLv3

test-requirements.txt

@@ -6,13 +6,7 @@ ansible-lint>=3.0.0,<6.0.0,!=4.3.0 # MIT
 bashate>=0.2 # Apache-2.0
 coverage>=4.0 # Apache-2.0
 doc8 # Apache-2.0
-docker # Apache-2.0
 hacking>=3.0.1,<3.1.0 # Apache-2.0
-molecule # MIT
-molecule-docker # MIT
 oslotest>=1.10.0 # Apache-2.0
-paramiko
-pytest-molecule # MIT
-pytest-testinfra
 stestr # Apache-2.0
 yamllint # GPLv3

tox.ini

@@ -62,7 +62,7 @@ commands =
 deps =
     -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/wallaby}
     -r{toxinidir}/requirements.txt
-    -r{toxinidir}/test-requirements.txt
+    -r{toxinidir}/molecule-requirements.txt
 whitelist_externals =
     bash
 commands =

zuul.d/jobs.yaml

@@ -9,6 +9,7 @@
     irrelevant-files:
       - ^.*\.rst$
       - ^doc/.*
+      - ^molecule-requirements.txt
       - ^releasenotes/.*
       - ^setup.cfg$
       - ^zuul.d/.*
@@ -25,6 +26,7 @@
     irrelevant-files:
       - ^.*\.rst$
       - ^doc/.*
+      - ^molecule-requirements.txt
       - ^releasenotes/.*
       - ^setup.cfg$
       - ^zuul.d/.*
@@ -71,6 +73,7 @@
     irrelevant-files:
       - ^.*\.rst$
       - ^doc/.*
+      - ^molecule-requirements.txt
       - ^releasenotes/.*
       - ^setup.cfg$
       - ^test-requirements.txt