clean up tests in preparation for ports-of-call variant transition

[Yurlungur]

PR Summary

This MR is motivated by #590 , where test_pte was failing. I tracked this down to LLVM versions < 19, which apparently produce problematic device code. Now for AMD GPU builds, if the clang compiler version is less than 19, this test is disabled and a warning is emitted.

In the process, I also cleaned up a few minor things:

• test_pte.cpp has been re-written slightly for clarity. The main test function no longer returns any values, but sets relevant quantities by reference.
• test_spiner_transform.cpp was being improperly compiled when spiner was enabled by HDF5 was not. This has been resolved.

PR Checklist

• Adds a test for any bugs fixed. Adds tests for new features.
• Format your changes by using the make format command after configuring with cmake.
• Document any new features, update documentation for changes made.
• Make sure the copyright notice on any files you modified is up to date.
• After creating a pull request, note it in the CHANGELOG.md file.
• LANL employees: make sure tests pass both on the github CI and on the Darwin CI

If preparing for a new release, in addition please check the following:

• Update the version in cmake.
• Move the changes in the CHANGELOG.md file under a new header for the new release, and reset the categories.
• Ensure that any when='@main' dependencies are updated to the release version in the package.py