Optimizing build

[acse-bn20]

I changed make to ninja. This results in 20-30% faster build time than the previous one. It successfully compiled on Narval.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[jbrillon]

Since this is your first PR, post the ctest results and we'll merge it

[acse-bn20]

output_ctest.log
I uploaded the local ctest results.

[cpethrick]

There are a few tests failing which usually don't fail (at least to the best of my knowledge!). Could you confirm the behaviour of the following tests?

1D_TIME_REFINEMENT_STUDY_ADVECTION_IMPLICIT
1D_DIFFUSION_BR2_IMPLICIT_MANUFACTURED_SOLUTION
ANISOTROPIC_MESH_ADAPTATION_SSHOCK (** this one may be due to your GMSH version if I recall correctly. It may pass if you change to GMSH 4.11.1.; see discussion on the test cases channel on discord. If you have a different GMSH, it's fine to leave this failing)

I checked and these tests pass on the current master.