When encryption context was changed for a attachment using SysAttachment.changeEncryptionContext API, system corrupts the attachment, when user doesn't have access to encryption context (to which it is being changed to).
Steps to Reproduce
* create 2 encryption contexts: EC1 and EC2
* create an admin user with role that grants access to EC1, but don't grant access to EC2
* add an encrypted attachment to an existing incident -> use EC1
* run script to use changeEncryptionContext API to attempt to change the encryption context to EC2
* after running the script, download the attachment and see that is corrupt
Related Problem: PRB1252502