Make rucio-init idempotent

[maxnoe]

Running rucio-init a second time results in errors, i.e. "duplicate key value violates unique constraints VOS_PK".

It would be great for test setups if rucio-init would be idempotent

[bari12]

Hi @maxnoe
Took us a while, but we are looking into this. Why are you running this init container multiple times? The idea is it sets up the environment once, and that's it? And if you could run it multiple times, what would be your expectation? Reset of the database and start at 0, or just do nothing?