Preserve the relative paths of license files

[L-TChen]

As suggested in #9172, I propose an independent PR to resolve #9184, which removes the use of takeFileName while copying license files.

It also moves the definition of paths of copied license files to the module Distribution.Simple.BuildPaths, as other packages might use this definition to determine the location of license files.

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Template Α: This PR modifies cabal behaviour

Include the following checklist in your PR:

• [x] Patches conform to the coding conventions.
• [x] Any changes that could be relevant to users have been recorded in the changelog.
• [x] The documentation has been updated, if necessary.
• [x] Manual QA notes have been included.

Bonus points for added automated tests!

[geekosaur]

The Validate thing is a bug in the new unix package. It's been marked uninstallable until a new release is made, so CI should work now.

[L-TChen]

Could there be a test demonstrating the new behavior?

I'd love to, but I am not able to run cabal-tests in the package cabal-testsuite locally, even though I have followed the instruction documented in cabal-testsuite/README.md. It always complains

: cannot satisfy -package-id Cabal-3.11.0.0-inplace

Any hint?

[andreasabel]

@L-TChen For me, the instructions work:

cabal build all
cabal run cabal-testsuite:cabal-tests -- --with-cabal=cabal cabal-testsuite/PackageTests/TestOptions/setup.test.hs

[ffaf1]

@L-TChen did you manage to compile it? Can we help?

[L-TChen]

@L-TChen did you manage to compile it? Can we help?

Yes, thanks for asking. I managed to run the test suite locally, but I just did not have the time to complete it.

[gbaz]

Is this still pending a test?

[ffaf1]

@L-TChen If you need a hand with writing tests, I can do it!

[Mikolaj]

@L-TChen: ping! ping! we want to help! :)