Can Ansible porting guide say which version of core is included?

[samccann]

Seems this detail is in the changelogs - https://github.com/ansible-community/ansible-build-data/blob/main/4/CHANGELOG-v4.rst#id867

But that's a bit buried. Would be great if we could put it at the top of the porting guide as well - https://docs.ansible.com/ansible/devel/porting_guides/porting_guide_5.html#ansible-5-porting-guide
Maybe just add a heading 'ansible-core 2.12 Porting Guide' and put all that detail under that new header?

[felixfontein]

A simple fix is to mention it similarly as in the case where two consecutive Ansible major releases have the same ansible-core major release (https://github.com/ansible-community/antsibull/blob/1f621e65c55ebb4b2fdab710f1bda5fa9c4f276a/src/antsibull/build_changelog.py#L653). I've implemented that in #397.