Fixes ssg/utils.py to parse version numbers

[shawndwells]

When we first wrote ssg/utils.py we assumed product names would never contain numbers. So it worked for names like:

rhel9 -> rhel + 9
ubuntu2404 -> ubuntu + 2404

But it failed for names like bascontrol22d4 because the prefix itself contains digits (22) before the final version digit (4).

This patch fixes that and we now can capture the shortest possible prefix then capture the final run of digits at the end of the string.

So now:

bascontrol22d4 -> bascontrol22d + 4

That matters because the build system uses this parser to derive product name and version pieces for labels, IDs, and generated content. Without the change, products with numbers in their name break the building system.

This patch updates that regex to make product IDs with digits in the middle valid, as long as they still end with a numeric version.

[shawndwells]