Add Github Actions from packages feed

This comes from the OpenWrt packages repository and added a few changes,
which were not merged, yet. E.g. in packages feed, there is run test in
Docker container if there is dedicated file test.sh near Makefile, but
there is a pending change to be merged to run generic run test to check
version of package even there is no test.sh

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>