fix unit tests by not cleaning up all $EASYBUILD_X env vars, only the ones that matter
bump required version of Lmod to v5.6.3
bump required version of modulecmd to 3.2.10, since we are aware of bugs/missing features in earlier versions
Merge pull request #963 from boegel/fix_unit_tests

fix unit tests by not cleaning up all $EASYBUILD_X env vars, only the ones that matter