* Use runners on HPC instead of fake.

* The version currently available via Alpine Linux are all affected by
  a bug that leads to non-resolved references.
* Doxygen versions 1.9.5 to 1.11.0 exhibit the buggy behaviour.
* Will switch back to doxygen CI-Container once 1.12 or newer is
  installed there.

* Why the startup of Intel MPI fails in the container running the CI still
  needs investigation.

* It currently does not work in Docker.

* Use NAG 7.1 in CI setup instead of 7.2 because 7.2 is not yet
  supported in the Docker image.
* Use our libtool patches for autoreconf (required for working NAG builds).

* This will also catch files where the name is composed of tabs and spaces.

* Also remove flag that configure can deduce by itself.