Test PyPI dry-run deploy doesn't overwrite the package once it's deployed

[PawelLipski]

Since some of the following steps in dry-run deploy depend on test PyPI, they always use the first-ever uploaded package for the given version :/

Proposed solution: use development versions with some suffix, like 3.7.2-10-ab45cd23 (with number of commits since the latest tag + latest commit hash).