Convert master->main dflt branch in all related repos

[scottkurz]

See: https://github.com/OpenLiberty/application-stack/wiki/Links for list of related repos

[mezarin]

Convertion of https://github.com/OpenLiberty/application-stack-starters is blocked by:
https://github.com/openshift/odo/issues/4555

[scottkurz]

Let me checkpoint here and say we at least looked at this and didn't find a trivial answer.

The odo #4555 has been closed. Also redhat-developer/odo#4257 was merged.

Our problem isn't resolved by allowing you to specify a specific branch in the devfile. We're making the different point that odo should be able to honor GitHub 's view of the default branch, just like git clone seems to.

I'm not sure what has/hasn't been fixed.

This is non-trivial and we'll have to follow-up more later.