Fix incorrect expectedUTxO assertion in DirectChainSpec fanout test (#2521)
The `expectedUTxO` unconditionally included `utxoToCommit`, but when
`snapshotVersion == v` (no `Increment` was posted), the fanout correctly
excludes `utxoToCommit`.
We didn't notice the test flaw because it was hidden, because both
`someUTxO` and `someUTxOToCommit` used identical values (2M lovelace),
so `containsOutputs` matched on TxOut content.
This PR aligns `expectedUTxO` with the actual fanout logic. It uses
different lovelace amounts so we will not be tricked by the hidden
mismatch.
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