consensus: TestReactorValidatorSetChanges test fix (#7985)

internal/consensus/reactor_test.go

@@ -2,6 +2,7 @@ package consensus
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"path"
@@ -198,7 +199,11 @@ func waitForAndValidateBlock(
 		require.NoError(t, validateBlock(newBlock, activeVals))
 
 		for _, tx := range txs {
-			require.NoError(t, assertMempool(t, states[j].txNotifier).CheckTx(ctx, tx, nil, mempool.TxInfo{}))
+			err := assertMempool(t, states[j].txNotifier).CheckTx(ctx, tx, nil, mempool.TxInfo{})
+			if errors.Is(err, types.ErrTxInCache) {
+				continue
+			}
+			require.NoError(t, err)
 		}
 	}