Fixes https://github.com/twentyhq/core-team-issues/issues/52
- contrary to title, we do not remove serverless functions on workflow
version archivation because serverless fucntion might be used in another
workflow version
- we fix the serverless funciton version displayed in the code step
- we allow test function version in step display right drawer
- we delete serverless function only when serverless function has no
published version