Add tox env for update-test-platforms

It seems some versions of ruamel do a better job at preserving
comments than others.  Create a tox env to regenerate the lists with a
version we know works.

Change-Id: I13503890fd3c18487281e3394b003e9f36cd24f2

tox.ini

@@ -74,4 +74,11 @@ exclude =
   *.egg,
   # vendored files
   roles/use-buildset-registry/module_utils/pytoml.py,
-  roles/use-buildset-registry/module_utils/remarshal.py
+  roles/use-buildset-registry/module_utils/remarshal.py
+
+[testenv:update-test-platforms]
+basepython = python3
+deps =
+  ruamel.yaml>=0.16.7
+commands =
+  python ./tools/update-test-platforms.py

zuul-tests.d/cloud-roles-jobs.yaml

@@ -9,7 +9,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/container-roles-jobs.yaml

@@ -207,7 +207,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/general-roles-jobs.yaml

@@ -462,7 +462,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/go-roles-jobs.yaml

@@ -10,6 +10,11 @@
     vars:
       go_command: version
 
+# -* AUTOGENERATED *-
+#  The following project section is autogenerated by
+#    tox -e update-test-platforms
+#  Please re-run to generate new job lists
+
 - project:
     check:
       jobs: &id001

zuul-tests.d/jobs.yaml

@@ -12,7 +12,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/js-roles-jobs.yaml

@@ -9,7 +9,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/launchpad-roles-jobs.yaml

@@ -13,7 +13,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/puppet-roles-jobs.yaml

@@ -9,7 +9,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - project:

zuul-tests.d/python-jobs.yaml

@@ -19,7 +19,7 @@
 
 # -* AUTOGENERATED *-
 #  The following project section is autogenerated by
-#    tools/update-test-platforms.py
+#    tox -e update-test-platforms
 #  Please re-run to generate new job lists
 
 - job: