Incorrect version suffix for non-stable releases

[Craig Duncan]

I see a change was made in baa3a37 which respected the version string from the extension.
However it looks like this was reverted in f2548dc which is now causing issues like microsoft/msphpsql#1210 (Invalid version string "5.9.0beta2-beta")

Does anybody know why f2548dc was committed?

[Michele Locati]

This issue should have been fixed by #201