'Upcoming cards' not showing cards assigned to my teams / groups

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Describe the bug
As we now have support for assigning teams (https://github.com/nextcloud/deck/issues/4716) and groups to a card, we have to make sure that all members of the assigned teams or groups (including sub-teams and their members) get to see the card in their 'Upcoming cards' view.

To Reproduce
Steps to reproduce the behavior:

1. Create a new card in some board
2. Assign a card to a team or a group that you are a member of
3. Go to 'Upcoming cards' and see how the card is not displayed there

Expected behavior
The card should be displayed for all the members of assigned teams and groups

Start by reproducing the issue in the Upcoming cards view after assigning a card to a team or group, including a sub-team if relevant. Trace how Upcoming cards determines whether the current user can see assigned cards, then verify that all members of assigned teams and groups see the card and that existing behavior remains intact.