Unable to add Team selection to a custom attribute

[DHaussermann]

When adding or updating a custom attribute the team selection no longer finds any results even when there are team names that mach the search parameter.

Steps:

• Build and deploy the master branch of the plugin
• Note the name of an existing team ex: dkh
• Navigate to custom attribute settings
• Add a new custom attribut
• search for dkh as a team to target with the custom attribute
  Expected: DKH is returned
  Observed:
  A. No teams are returned
  B. Console shows a 400 error
  

[DHaussermann]

This may be related to #63 but I am not quite seeing the same behavior as retrieving users in the search is working as expected.

[nathanaelhoun]

@DHaussermann what mattermost server version are you using?

[DHaussermann]

@nathanaelhoun I have reproduced this on v5.37.3 and v6.0.0.
I have double checked that this occurs in master branch and not the latest production release of v1.3.0