ExemptDivision is kinda non-deterministic

From !9642 (merged) and https://openpl.zulipchat.com/#narrow/stream/137812-git/topic/OpenPowerlifting.20.2F.20MR.20.239642.20Add.20365Strong.20Kentucky.20State/near/436557759:

if two meets occur on the same date, the checker will pass if the exemption is only set for the meet that appears first in the arbitrary check-duplicates sort order. This isn't intentional and that logic isn't stable. The check-duplicates logic should exempt the meet in both cases, when it's in the A->B case, and in the B->A case. Right now it just does A->B for [A,B].