Provide the binding class to make credentials be usable with withCredentials pipeline function

### What feature do you want to see added?

I want to avoid credentials duplication and use the same item in job pipeline.
Unfortunately, "OpenstackCredentialv3" does not provide a binding class, so the only way to reuse credentials looks like:
```
def os_all_creds = com.cloudbees.plugins.credentials.CredentialsProvider.lookupCredentials(
jenkins.plugins.openstack.compute.auth.OpenstackCredentialv3
)
def os_credential = os_all_creds.findResult { it.id == "my-openstack-credentials" ? it : null }
```

The minor part of the hack relates to the fact that the credentials are not excluded from job run output.

### Upstream changes

_No response_

### Are you interested in contributing this feature?

_No response_