Bump cabal-testsuite Cabal version to 3.18.1.0

[fendor]

Allows us to use --with-repl in the Cabal codebase.

Without it, cabal currently cannot be loaded into HLS with cabal 3.18.1.0.

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Template B: This PR does not modify behaviour or interface

E.g. the PR only touches documentation or tests, does refactorings, etc.

Include the following checklist in your PR:

• Patches conform to the coding conventions.
• Is this a PR that fixes CI? If so, it will need to be backported to older cabal release branches (ask maintainers for directions).

[fendor]

See #12186 for context :)

[fendor]

Looks like this needs a change to the cabal-testsuite to properly support Cabal 3.18 (or 3.16 for that matter which seems to be required by the alpine job).

[ulysses4ever]

Thanks!

The fact that it stalled at 3.12 points to the incompleteness of our wiki page on releasing cabal.