Shared with column in "Shared with others" should contain multiple users

[PVince81]

Steps

1. Create three users "Alice", "Bob" and "Charlie"
2. Login as "Alice"
3. Share a folder "test" with both "Bob" and "Charlie"
4. Open the "Shared with others" panel
5. Look at the "Shared with" column for the "test" folder

Expected result

Both "Bob" and "Charlie" appear there, separated with a comma.
If more than three users or groups, show an ellipsis for the fourth one (check product requirement there)

Actual result

Only "Charlie" appears.

The network response does contain two entries so it's a frontend issue.

@pmaier1 FYI

[PVince81]

PR here: #3049

[PVince81]

I went a bit overboard... I've noticed that link shares are now also included so I went a bit further and tried to add some distinction.

In my first attempt (the before last commit), shows share indicators:

Please note that we cannot show indirect shares there due to performance reasons.

And another further attempt (last commit) with the collaborator list:

I don't think I'll go further there but we can use this as input for further designs.
As the goal was to just fix the list of collaborators, I might split this PR into "current fix" and "future stuff".

@pmaier1 @LukasHirt

[LukasHirt]

It feels a bit weird seeing the link in collaborators column but I understand that it needs to be there 🙈

[PVince81]

next iteration here, looks a bit better now with avatars: #3049 (comment)