Clarify DRD docs - id vs. name

[akeller]

In the DRD docs, we received feedback that a section might be misleading.

• Change the admonition to something bolder (info or caution)
• Adjust the language not to imply this is optional (as in, user read it an assumed it was optional)

Internal Slack discussion - https://camunda.slack.com/archives/C026U8GBNSW/p1706189870641629