Requires prj files to be given as array, e.g:
project = ["project1.prj", "project2.prj"]

and a symlink of Tests into web (super ugly) as hugo cannot access files
outside of its working directory.

Restructuring of the TRM process: Split constitutive setting

See merge request ogs/ogs!4198

[CL] add a new type of chemical solver "self-contained chemical solver"

See merge request ogs/ogs!4207