Various fixes for build environments (Flang, Windows) and XML

Changed

• Add an enclosing <testsuites> element an xml version/encoding element in the funit xml output. Makes the output readable by more CI systems (Jenkins, GitLab-CI).
• Change CMake from using PARENT_SCOPE to CACHE INTERNAL as it seems in some setups using
  pFUnit via FetchContent the former does not work as expected.
• Update some COMMENT lines in functions with double-quotes to avoid warnings

Fixed

• Fix parser on Windows for paths with different drive letters
• Updates for CMake versions newer than 3.30.
• Update NVHPC CI (build only)
• Fix CMake for LLVM Flang
• Update object library dependency handling (see #495)

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What's Changed

• Add correct header/footer to junit xml output by @melven in #493
• COMMENT takes exactly one argument by @td-mpcdf in #507
• Fix parser on Windows for paths with different drive letters by @melven in #506
• CI: Test NVHPC by @mathomp4 in #504
• Fixes #483. Move to use CACHE INTERNAL by @mathomp4 in #485
• Fixes for LLVM Flang by @mathomp4 in #509
• Fixes #495. Update object library dependency handling by @mathomp4 in #497
• GitFlow: Merge Develop into Main for 4.14 release by @mathomp4 in #510

Full Changelog: v4.13.0...v4.14.0