Before this change the count of volunteers in a team was not in sync with the filters applied.
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After the change:
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BTW I feel that we will end up refactoring the relation at some point in the future.
Reviewed-on: #46
Co-authored-by: Tocho Tochev <tocho@tochev.net>
Co-committed-by: Tocho Tochev <tocho@tochev.net>