prerelease bats tests do not correctly check the displayed version for any prerelease with date

[tyler-jachetta]

The prerelease tests in bats that are checking --prerelease-date, use git -v with an extended pattern (but no -E) to check the output, so the tests as-is will always succeed unless something really strange is output.

I tested this locally by making avakas show print 'foo'. All of the date tests which use this pattern passed