Turn off check_solvable in CUDA 12 migrator

[jakirkham]

Usually check_solvable is set to false in other CUDA migrators, this was missed in PR ( #4400 ). Adding it here.

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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-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.

[github-actions]

Hi! This is the friendly conda-forge automerge bot!

I considered the following status checks when analyzing this PR:

• linter: passed
• azure: passed

Thus the PR was passing and merged! Have a great day!

[jakirkham]

The package upload from main appeared to be corrupted (package couldn't be viewed or downloaded though did show up on Anaconda.org). Just removed the package and restarting CI. Guessing some issue occurred on the Anaconda.org side during upload

[jakirkham]

A new package is up and appears to download without issues. So think this is now resolved