Update release-stratum.sh for 21.10 release (#839)
Update release-stratum.sh for 21.10 release (#839)

- Fix bcm Docker image names and tags
- Build and push p4c-fpm and stratum-tools packages and containers
- Fix Github logout
stratum/stratum,stratum/stratum,stratum/stratum,stratum/stratum,stratum/stratum,stratum/stratum