modemmanager: fix custom initial EPS bearer username - #30543

Checking PR #30543: modemmanager: fix custom initial EPS bearer username (Formalities Audit)

✅ Pull request originates from a dedicated feature branch (fix/modemmanager-init-username)

Commit be28dc1 - modemmanager: fix custom initial EPS bearer username:

✅ Author and committer identities are valid
✅ Commit is not a merge commit
✅ Commit subject layout and length are valid: "modemmanager: fix custom initial EPS bearer username"
✅ Commit description lines adhere to width formatting rules
✅ Commit contains a valid 'Signed-off-by:' line matching author or committer
⚠️ Warning: No reference link (e.g., upstream release notes, changelog, or history URL) detected in description.
⚠️ Warning: Commit is unsigned or cryptographic signature verification failed (Reason: unsigned). Signing commits is a recommended best practice for verifying identity, but is not mandatory.