With the prior format, 1.33.0 / 1.33.1 / 1.33.2 got separate branches:
release-v1.33.0
release-v1.33.1
release-v1.33.2
Under the new model, all three would share a common branch:
release-v1.33
As before, RCs and actual releases exist as tags on these branches.
This better reflects our support model, e.g., that the "1.33" series had
a formal release followed by two patches / updates.
Signed-off-by: Dan Callahan <danc@element.io>