fix: shorebird release android with multi dimensional, multi word flavor breaks

[erickzanardo]

Description

When trying to release an app with multi dimensional and multi word flavor, for example: stable + playStore = stablePlayStore, the shorebird release command breaks.

Steps To Reproduce

1. Go to the multi dimensional sample app
2. Run shorebird release android --flavor stablePlayStore
3. See error

Expected Behavior

Release should work

Screenshots

If applicable, add screenshots to help explain your problem.

Additional Context

This issue is happening because of a bug upstream in the flutter tool, there is an issue filled for it: flutter/flutter#147261