Bugfix: Fixed issues in git flavor pre release bumps

This patch fixes an issue where avakas would treat pre-releases as being releases in the git flavor

maintenance release

Merge pull request #65 from tyler-jachetta/tjachetta/test_in_containers

change: added `make test_in_containers` target to use Python docker containers for integration tests

1.0.13

Fixed #68 , so that git flavored autobumps do not create death spirals of fun

1.0.12: Merge pull request #70 from tyler-jachetta/fix_prerelease_issue_63

Fixed issues #63 so, fixes bug where prereleases never were incremented,

1.0.11

Merge pull request #57 from otakup0pe/mjuarez/fix-dogfooding

add testenv step