500 error if viewer tries to lock file

[ScharfViktor]

Steps:

• user creates file and shares file with viewer permissions to einstein
• einstein tries to lock file

or

• viewer- member of space tries to lock file inside of space

curl -XLOCK "https://localhost:9200/dav/spaces/fileUUID" -ueinstein:relativity -H "Content-Type: application/json" -H "timeout: Second-30" -d"<?xml version='1.0' encoding='UTF-8'?><d:lockinfo xmlns:d='DAV:'><d:lockscope><d:shared/></d:lockscope></d:lockinfo>" -vk

Expected: 403
Actual: 500 error