Error if replset name has upper-case letters in it

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We're trying to migrate from an existing cluster to using the operator. The repl set name starts with RS-, using upper-case letters. When we try to create the database using this operator we get an error because it uses the replsetname as part of the created service name, but service names cannot have upper-case letters in them in kubernetes.

More about the problem

Error: reconcile services: reconcile replset services: create or update
    service for replset RS-stagingdb-0: Service "stagingdb-RS-stagingdb-0" is
    invalid: metadata.name: Invalid value: "stagingdb-RS-stagingdb-0": a
    DNS-1035 label must consist of lower case alphanumeric characters or '-',
    start with an alphabetic character, and end with an alphanumeric character
    (e.g. 'my-name',  or 'abc-123', regex used for validation is
    '[a-z]([-a-z0-9]*[a-z0-9])?')

Steps to reproduce

Versions

1. Kubernetes 1.30
2. Operator 1.20.1
3. Database mongodb

Anything else?

It seems like the operator assumes that the replset names will also be valid kubernetes identifier prefixes, but in our case that is not true.

No file or test is named. Start by tracing service reconciliation and how the replica set name becomes a Kubernetes Service metadata.name; reproduce the uppercase RS- case on Kubernetes 1.30 and identify the existing naming path. Done means the operator can create valid services for uppercase replica set names, with regression coverage for this input.