staging PR for EasyBuild installation in zen4 + updated archspec file didn't show full overview of tarball contents

[boegel]

see https://github.com/EESSI/staging/pull/1235 (note: private repo), which was used for deploying both the changes from EESSI/software-layer#451 + EESSI/software-layer#547

Only 2023.06/init/arch_specs/eessi_arch_x86.spec is shown in overview of tarball contents, the EasyBuild installation + module file located in 2023.06/software/linux/x86_64/amd/zen4/software was not included for some reason...

Those files are listed in the overview produced by the bot though, see EESSI/software-layer#547 (comment)

[bedroge]

The code for generating the overview only works well for tarballs that only contain software, see:
https://github.com/EESSI/filesystem-layer/blob/main/scripts/automated_ingestion/eessitarball.py#L99
In this case the tarball also included init files from the root of the repo, and then the os.path.commonprefix doesn't work anymore.

But maybe we can easily reuse the same code that the bot uses to produce a tarball overview.

[boegel]

should be fixed by #195, so closing...