Set requirements branch for IPA build

Currently we use the HEAD reference for OpenStack requirements. This can
create images that are incompatible with your version of OpenStack.

See:
https://review.opendev.org/c/openstack/ironic-python-agent-builder/+/688911

Change-Id: I42026fafb1be0071f5ec94e81881c4a3bdd34af8
Story: 2009810
Task: 44371

ansible/group_vars/all/ipa

@@ -47,6 +47,7 @@ ipa_build_dib_env_default:
   DIB_RELEASE: "8-stream"
   DIB_REPOLOCATION_ironic_python_agent: "{{ ipa_build_source_url }}"
   DIB_REPOREF_ironic_python_agent: "{{ ipa_build_source_version }}"
+  DIB_REPOREF_requirements: "{{ openstack_branch }}"
 
 # Dictionary of additional environment variables to provide to Diskimage
 # Builder (DIB) during IPA image build.

doc/source/configuration/reference/ironic-python-agent.rst

@@ -58,9 +58,10 @@ image build``.
 ``ipa_build_dib_env_default``
     Dictionary of default environment variables to provide to Diskimage Builder
     (DIB) during IPA image build. Default is
-    ``{"DIB_RELEASE": "8-stream", "DIB_REPOLOCATION_ironic_agent": "{{
-    ipa_build_source_url }}", "DIB_REPOREF_ironic_agent": "{{
-    ipa_build_source_version }}"}``.
+    ``{"DIB_RELEASE": "8-stream", "DIB_REPOLOCATION_ironic_python_agent": "{{
+    ipa_build_source_url }}", "DIB_REPOREF_ironic_python_agent": "{{
+    ipa_build_source_version }}", "DIB_REPOREF_requirements": "{{
+    openstack_branch }}"}``.
 ``ipa_build_dib_env_extra``
     Dictionary of additional environment variables to provide to Diskimage
     Builder (DIB) during IPA image build. Default is empty.

releasenotes/notes/specify-requirements-branch-for-ipa-build-c3ca977ec21b58f4.yaml

+---
+fixes:
+  - |
+    Deployment image (IPA) build no longer uses master version of
+    upper-constraints. Instead, it defaults to using the constraints for the
+    OpenStack release associated with the version of Kayobe being used. See
+    `story 2009810 <https://storyboard.openstack.org/#!/story/2009810>`__ for
+    details.