updateinfoxml: workaround memory problem when adding to two flexarrays

[kontura]

When directly adding packages and modules to both pd->handle and pd->collhandle flexarrays right after each other repodata_add_array has to constantly move data in data->attriddata. It wastes a lot of memory.

For example running updateinfoxml2solv on fedora 38 updates repo updateinfo uses ~30 MiB vs ~604 MiB (without patch) at usage peak.

[vpodzime]

Nice! :clap:

[mlschroe]

I would have preferred to fix the underlying problem with the add_array, by I don't see no easy way to do this. I did change your patch to just use one queue that stores both the type and the handle id.

Thanks a lot!