CI_MERGE_REQUEST_TARGET_BRANCH_NAME is not available at parse time :(

The dockerfiles will be subsequently placed in /dockerfiles/.

Including the same YaML file multiple times is allowed since GitLab 14.9,
https://about.gitlab.com/releases/2022/03/22/gitlab-14-9-released/#include-the-same-cicd-template-multiple-times

Update coverage report syntax

See merge request omegacen/ci-templates!52

The old syntax has been removed in GitLab 15.0.
See https://docs.gitlab.com/ee/update/removals.html#artifactsreportcobertura-keyword.

Add option to specify conda build engine (default "build", other option "mambabuild")

See merge request omegacen/ci-templates!51