Fix the 2 known bugs in suit build script.
1. `checkoutFirefly` is suppose to switch to the branch given in the 'firefly_build.tag' file. However, it does it only on first build. Rebuilding suit again with a different tag did not work.
2. suit's build depends on project 'firefly_data'. It should trigger that build first but is not. This happens only on the very first run of the build. We were able to workaround this by running the build again. But, this should be fixed.