CMake: use CXX_COMPILER_LAUNCHER instead of RULE_LAUNCH_COMPILE

[Be-ing]

This allows for removing the hack for RULE_LAUNCH_COMPILE with
sccache.
https://gitlab.kitware.com/cmake/cmake/-/issues/22405

[coveralls]

Pull Request Test Coverage Report for Build 1020536608

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 11 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.01%) to 28.627%

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Files with Coverage Reduction	New Missed Lines	%
src/engine/readaheadmanager.cpp	2	88.79%
src/engine/cachingreader/cachingreader.cpp	9	71.38%

Totals
Change from base Build 1019395588:	-0.01%
Covered Lines:	20088
Relevant Lines:	70172

---

💛 - Coveralls

[daschuer]

Cool, it still works here on Ubuntu. Judged from the Windows build time running since 43 min by now it does not work for windows.
Can a windows contributor confirm that?

[Be-ing]

The long build time was because there was no cache for the branch yet.

[Be-ing]

I just asked upstream for a new release so we can install from Chocolatey instead of taking 10 minutes to build sccache from source.

[Be-ing]

I am confused why GitHub Actions keeps having cache misses.

[uklotzde]

Merge and keep an eye on Windows build times to detect possible regressions?

The new version is recommended and cleaner.

[daschuer]

Yes, I have just compared with other PRs and it is always around 50 min. This is suspicious, but no regression.