Fix current-version

[Strobotti]

This PR fixes the issue where multiple release tags pointing to same commit doesn't return the latest tag deterministically. The issue is presented here:

$ git for-each-ref "refs/tags/v*" --sort -creatordate --format "%(refname:short) %(creatordate)" --count 5

v0.13.10 Tue Jan 7 16:27:06 2025 +0200
v0.13.11 Tue Jan 7 16:27:06 2025 +0200
v0.13.9 Tue Jan 7 16:27:06 2025 +0200
v0.13.8 Tue Jan 7 15:08:26 2025 +0200
v0.13.7 Tue Jan 7 14:55:10 2025 +0200

The count is here set to 5 to demonstrate the order in which the tags are returned.

The fix merely adds "-version:refname" -sort to the mix and thus always returns the biggest version number as the top result if there are multiple "latest tag" -candidates to choose from:

$ git for-each-ref "refs/tags/v*" --sort -version:refname --sort -creatordate --format "%(refname:short) %(creatordate)" --count 5

v0.13.11 Tue Jan 7 16:27:06 2025 +0200
v0.13.10 Tue Jan 7 16:27:06 2025 +0200
v0.13.9 Tue Jan 7 16:27:06 2025 +0200
v0.13.8 Tue Jan 7 15:08:26 2025 +0200
v0.13.7 Tue Jan 7 14:55:10 2025 +0200