📖 Update CAPI support and guarantees for v1.12

[wendy-ha18]

What this PR does / why we need it:

• This PR updates the supported versions for the release cycle 1.12 (reference this: 📖 Update CAPI support and guarantees for v1.10 #11703)

As @fabriziopandini has clean up and consolidate version support in this PR: #11914, so I'm not update CONTRIBUTING.md as guided in the handbook, I only updated the docs/book/src/reference/versions.md

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #
Part of #12771

/area documentation

cc @chandankumar4 @sbueringer

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[sbueringer]

/assign @fabriziopandini

Not sure if we want to have a fourth column and then update this doc again after the 1.12 release.
I would prefer if we would minimize the number of updates we have to make to this doc

[fabriziopandini]

@wendy-ha18 thanks for this PR!

I think that at this stage of the release we should start getting the documentation on main ready for when v1.12 is going GA. As a consequence:

• v1.12 and v1.11 are the release in the standard support period
• v1.10 is in the maintenance support period
• v1.9 is EOL and should be dropped from tables

wdyt?