Capital letters in username makes the operator crash

Please, answer some short questions which should help us to understand your problem / question better?

• Which image of the operator are you using? e.g. ghcr.io/zalando/postgres-operator:v1.12.0
• **Where do you run it - self hosted kubernetes on vmware provisioned infra
• Are you running Postgres Operator in production? yes
• Type of issue? Feature request

When I deploy a postgres cluster with a username containing capital letters, postgres operator faces runtime panic errors which makes the operator go into CrashLoopBackOff state, so even if one cluster has this issue in the CR, ultimately the operator will stop managing the lifecycle of all the clusters which shouldnt be the case.
Can this flow be improved?

One temporary fix I can think of is writing a gatekeeper validation policy, but then I think this is something that should be handled in the codebase of operator. Let me know if maybe I am overlooking something, happy to check the issue or reproduce the issue for easier understanding, can help with fixing this in oss as well if its something the maintainers think should be fixed.

maybe something relevant: https://www.postgresql.org/docs/7.0/syntax525.htm#:~:text=Names%20in%20SQL%20must%20begin,%2D9)%2C%20or%20underscores.

Start by reproducing the operator deployment with a PostgreSQL username containing capital letters and inspect where the operator handles that cluster. Done means the operator no longer panics or enters CrashLoopBackOff, and it continues managing the other clusters.