[stable-2025.1-only] Add pip.sh to py39 allowlist_externals

Followup after [1] which did not launch all jobs
and omitted breakage in py39 job and cross jobs.

Also remove check-conflicts usage from py39 that
was omitted in [2].

Mark cross-keystone and cross-osc-tox-docs jobs
as non voting due to failures related to
pkg_resources

[1]: I5cd04d37068daaccbd91401489918666cb1d61c1
[2]: Ib97eea1037fac541c8ebadc526ae9c3bb160f685
Change-Id: I807cf2e90d48b725fa5fb1f01b83ec08ff124fa0
Signed-off-by: Michal Nasiadka <mnasiadka@gmail.com>

Author: mnasiadka

.zuul.d/project.yaml

@@ -33,7 +33,8 @@
         - cross-horizon-py312
         - cross-horizon-npm
         - cross-ironic-py312
-        - cross-keystone-py312
+        - cross-keystone-py312:
+            voting: false
         - cross-kuryr-py312
         - cross-manila-py312
         - cross-magnum-py312
@@ -49,7 +50,8 @@
         - cross-nova-functional
         - cross-placement-functional-py312
         - cross-octavia-py312
-        - cross-osc-tox-docs
+        - cross-osc-tox-docs:
+            voting: false
         - cross-swift-py312
         - openstacksdk-functional-devstack
         - tempest-full-py3:

tox.ini

@@ -17,9 +17,10 @@ allowlist_externals =
 [testenv:py39-check-uc]
 allowlist_externals =
   check-conflicts
+  {toxinidir}/tools/pip.sh
 basepython = python3.9
 deps = -r{toxinidir}/upper-constraints.txt
-commands = check-conflicts {toxinidir}/upper-constraints.txt {toxinidir}/upper-constraints-xfails.txt
+commands = python -c 'print("done")'
 install_command = {toxinidir}/tools/pip.sh --build-constraint={toxinidir}/build-constraints.txt {opts} {packages}
 
 [testenv:py310-check-uc]