Bump conda-smithy selector to Python 3.12

[jakirkham]

Since this will be encountered again during the next Python migration, just bump the Python version in the downstream test selector. This way that migration can go through smoothly and we can bump once conda-smithy is installable with the next Python version.

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Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[isuruf]

This selector should not be necessary once mamba-org/boa@45e1752 is in a release.

[jakirkham]

It is in boa version 0.13.0. Should we include this as a lower bound somewhere?

[conda-forge-webservices]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[jakirkham]

Fixed the conflict. Though this won't work until conda-smithy is rebuilt with Python 3.12 or the fix Isuru alluded to above (or an equivalent fix) is available