Let's stop using an ancient and deprecated version.
Here is documentation for the library. https://fedora-modularity.github.io/libmodulemd/latest/
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1723263
Pungi using libmodulemd 1.x cannot coexist with createrepo_c 0.14+ which uses libmodulemd 2.x. So this issue may become urgent relatively soon.
Commit 61e3cb0e fixes this issue
This issue has been migrated to Fedora Forge: https://forge.fedoraproject.org/pungi/pungi/issues/1225
Please continue any further discussion there.