koji-upload: Replace - with . in versions

[darkmuggle]

Enforce NVR rules for Koji

[cgwalters]

Seems reasonable but, let's add the rationale here to both the commit message and a comment in the source file. Something like:

koji-upload: Replace `-` with `.` in versions

For RHCOS we are trying to make use of `-` as a version character in order to be semver-compatible.
See https://github.com/openshift/oc/pull/209#issuecomment-564876535

However, Koji rejects this, so we'll just convert it for now, accepting the divergence in version numbers.

And in the code:

# RHCOS wants to be semver-compatible, but Koji doesn't accept `-`.  See
# https://github.com/openshift/oc/pull/209#issuecomment-564876535

?

[darkmuggle]

Updated the commit message. Running this through the pipeline.

[darkmuggle]

Waiting for end-to-end testing.

[cgwalters]

This this one get tested? Seems safe enough to merge.

[jlebon]

Looks like this was merged as part of #1060.