Switch IPA building to Debian Bookworm

Depends-On: https://review.opendev.org/c/openstack/ironic-python-agent-builder/+/903175
Change-Id: I7de7841c9fb16379cce94ce08413483472284534

doc/source/install/index.rst

@@ -315,7 +315,7 @@ Bifrost supports the ability for a user to build a custom IPA ramdisk
 utilizing diskimage-builder and ironic-python-agent-builder. In order
 to utilize this feature, the ``download_ipa`` setting must be set to ``false``
 and the create_ipa_image must be set to "true".  By default, the install
-playbook will build a Debian Bullseye based IPA image, if a pre-existing IPA
+playbook will build a Debian Bookworm based IPA image, if a pre-existing IPA
 image is not present on disk. If you wish to explicitly set a specific release
 to be passed to diskimage-create, then the setting ``dib_os_release`` can be
 set in addition to ``dib_os_element``.

playbooks/roles/bifrost-create-dib-image/README.md

@@ -59,9 +59,9 @@ dib_os_release can be utilized to set the DIB_RELEASE environment
 variable for semi-dynamic disk image creation by a user or the
 test script.  By default, it is not set, but an example if
 dib_os_element is set to ``debian``, then a user could choose
-the ``bullseye`` release.
+the ``bookworm`` release.
 
-dib_os_release: bullseye
+dib_os_release: bookworm
 
 All the other command-line options to disk-image-create or
 ramdisk-image-create can be used by the role. The following is a list

playbooks/roles/bifrost-create-dib-image/tasks/main.yml

@@ -115,7 +115,7 @@
     - dib_packages | length > 0
 - name: "Set default of Debian Bullseye if building debian and not explicitly set, override with dib_os_release setting"
   set_fact:
-    dib_os_release: "bullseye"
+    dib_os_release: "bookworm"
   when: dib_os_element == "debian" and dib_os_release is undefined
 - name: "Initialize DIB source-repository variables"
   set_fact:

releasenotes/notes/debian-ipa-68a052f8d9b09816.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    Switches to Debian Bookworm for building IPA by default.