[Sharing NG]User tries to list permission of other user's personal space return 500 status code

[amrita-shrestha]

Describe the bug

User tries to list permission of other user's personal space using root endpoint return 500 status code

Steps to reproduce

1. user "Alice" has created a space "new-space"
2. user "Brian" tries to list the permissions of space "new-space" owned by "Alice" using root endpoint
3. returns HTTP status code 500

Expected behavior

HTTP status code 404

Actual behavior

HTTP status code 500

Setup

Please describe how you started the server and provide a list of relevant environment variables or configuration files.

ownCloud	Infinite Scale
Edition	Community
Version	5.1.0-prealpha+ceeb4ed71d
Web client version	9.0.0-alpha.5

Additional context

Add any other context about the problem here.