Enhancement: Added better logging for retired user error

[kalisp]

Changelog Description

Synchronizing Comment with '@RETIRED_USER_IN_SG' from AYON triggers nondescript:

shotgun_api3.shotgun.Fault: API create() CRUD ERROR #6: Invalid field value, update failed [5 - Update failed for [Note.addressings_to]: Value is not legal.]

This PR logs it more verbosely with:

ERROR: Failed to create SG Note for AYON activity 5729ead0fddd11f09fae591c14fdf166: Comment contains link to retired userin SG in '[{'type': 'HumanUser', 'id': 253}, {'type': 'HumanUser', 'id': 156}]

Testing notes:

1. retire account in SG that you have synchronized in AYON

2. reference that account in @ in Comment
3. unretire account from Trash > People