Add a container for Python 3.12.

[tvalentyn]

part of #30828 .

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[github-actions]

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[tvalentyn]

Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

Hmm, not seeing failures actually.

[tvalentyn]

assign set of reviewers

[github-actions]

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[github-actions]

Reviewers are already assigned to this PR: @jrmccluskey @damccorm

[damccorm]

Do we need to update

beam/sdks/python/container/build.gradle

Line 24 in 8328d07

int max_python_version=11

[tvalentyn]

thanks, done.

[damccorm]

LGTM, thanks!