Windows CI job goes out of memory when building tests

[SiarheiFedartsou]

We had to disable running unit tests on Windows in this PR. MSVC goes out of memory when trying to build tests:

2024-06-08T09:06:17.5884670Z D:\a\osrm-backend\osrm-backend\unit_tests\library\route.cpp(128,49): error C1060: compiler is out of heap space [D:\a\osrm-backend\osrm-backend\build\unit_tests\library-tests.vcxproj]

It seems it started happening after yet another update of CI base image.