Use recommended reproducibility options for tar

[sethmlarson]

Takes the reproducibility recommendations on tar archives from these sources:

• https://reproducible-builds.org/docs/archives/
• https://www.gnu.org/software/tar/manual/html_node/Reproducibility.html#Reproducibility

As individual options:

• Uses the commit time as the maximum mtime for tar filesystem metadata
• Sort the entries by name
• Set the uid and gid to 0 for tar filesystem metadata
• Omit all the unnecessary optional metadata
• Adds --no-name to gzip sub-command to avoid embedding the name and timestamp in the gzip stream

Using these options I was able to reproduce a build on GitHub Actions from the same build locally. Need to do more extensive testing using reprotest.