40536320ef
Add support in build shared workflow for per branch tools container.
With pr the target branch is parsed and the right container is used.
To use the stable container for local testing the branch needs to have
the prefix openwrt-[0-9][0-9].[0-9][0-9]- (example openwrt-21.02-fixup)
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
(cherry picked from commit abe8a48242)