Fixes CI job with poetry.

Default python on arch is 3.10; there are no vtk wheels for it,
required by VTUInterface.

When CAT_LOG=True the log is written to stdout instead of LOG_FILE.

Only call `poetry add` when there are new Python package requirements.

Based on initial implementation from @chleh.

[ci] Improved check header job.

See merge request ogs/ogs!3917

Will be yellow if failed.

[cmake] Select lld over GNU gold over regular linker.

See merge request ogs/ogs!3940