From T400666: SecurePoll: Cannot create BLT dump of encrypted election, BLTs are generated with the tally. Dump (BLT) should be deprecated because it doesn't support BLTs for encrypted elections or with post-election modifiers like candidate exclusions. In the former, it'll generate an unhelpful/incorrect error message and there's no way to prompt it to do the latter. Dumps should return to being just a return of the votes as they're represented in the database.

Acceptance Criteria:

• "Dump (BLT)" is no longer an option