Fix wrong definition of compiler launcher for CI.

4 jobs for <span class="ref-name">fix/wrong-definition-of-compiler-launcher-for-ci</span> in 23 minutes and 41 seconds (queued for 3 minutes and 41 seconds)
Status Job ID Name Coverage
  Test
passed #7847
docker-debian9
job-debian9-ninja-clang

00:05:33

passed #7846
docker-debian9
job-debian9-ninja-gcc

00:06:16

passed #7848
macosx
job-macosx-ninja

00:04:46

passed #7849
windows
job-windows-vs2015

00:11:57