SUPERSET_VERSION_RC might not be set and lead to failing tarball creation.

[Joel-Haeberli]

How to reproduce the bug

1. Execute [SOURCE_DIR]/RELEASING/make_tarball.sh in an environment you never used before and the release ENV-Variables are not set.

./make_tarball.sh [VERSION] [RC] [PGP_KEY_NAME]

2. The script fails with

gpg: can't open '/[YOUR_RELEASE_DIR]/svn/superset_dev/2.0.0rc2/apache-superset--source.tar.gz': No such file or directory
gpg: signing failed: No such file or directory

Expected results

I expect the script to build the correct versioned tarball.

Actual results

Tarball without the correct name leading to errors in the script which expects the name with the correct version.

Screenshots

see Point 2 in 'How to reproduce the bug'

Environment

• Theoretically all environments.
• Versions of browsers etc. not relevant.

Checklist

Make sure to follow these steps before submitting your issue - thank you!

• I have checked the superset logs for python stacktraces and included it here as text if there are any.
• I have reproduced the issue with at least the latest released version of superset.
• I have checked the issue tracker for the same issue and I haven't found one similar.

[rusackas]

@Joel-Haeberli we were checking in on that PR still, but is this still an issue at all as of Superset 3.x? We'll leave it open for now.