batches: remove pre-selected filters for batch changes list

Created by: courier-new

Removes the default filters selected on the batch changes list, restoring the initial behavior where all batch changes are shown (none are filtered).

This has the additional effect that for instances without server-side execution enabled (aka all current customer instances), all batch changes will also be shown there. This is different from the original behavior with the radio buttons (only open), but based on the discussion in Slack, I see no reason to treat pre-SSBC customers any differently.

I didn't bother to make a ticket for this one since it's so tiny of a change, and something we've gone back and forth on.

Test plan

Very limited scope of change. Verified manually that adding and removing a filter works as expected.