Add or strip the v prefix on git tags applied to golang projects

`go mod` requires that versions be prefixed with a lowercase v: https://github.com/golang/go/issues/32945

( more angry version: https://github.com/golang/go/issues/30146 )

Add various hacks throughout the CI system to add or strip the v as necessary to create tags in git that use the v#.#.# format, but create Docker containers and other artifacts without the preceding v.

VERSION and other files will continue as-is (won't have a preceding v)