Clean-up and simplify LauncherTests

[HannesWell]

No description provided.

[github-actions]

Test Results

   26 files   -  2     26 suites   - 2   11m 31s ⏱️ -32s
2 170 tests ± 0  2 118 ✅  -  6  46 💤 ±0  6 ❌ +6 
2 214 runs   - 28  2 162 ✅  - 34  46 💤 ±0  6 ❌ +6 

For more details on these failures, see this check.

Results for commit f70f118. ± Comparison against base commit a90c944.

[HannesWell]

I assume the test-failure is either due to the conversion to text-block (which uses the platform-specific line-separator instead of always \n) or maybe some charset issues due to the change in writeEclipseIni(). But I currently have don't have the nerve to investigate that.
Anyone interested, is welcome to pick this up, maybe also considering to convert this test-project into a 'regular' test fragment to get rid of the symbolic link to JNIBridge which also does not work well on windows.