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- Fixes incompatibility with transaction 2.4.0.
In transaction 2.4.0 some internal APIs we use have changed. As a result,
we've hade to make a small change. As there's probably no need to keep
an old transaction release around we dropped support for transaction < 2.4.0.
If you have a good reason why we should support an old transaction release
with the latest more.transaction, let us know - it could be done, though
there should be tests verifying multiple transaction releases against
more.transaction.
See https://github.com/zopefoundation/transaction/pull/68