Update unit test

Signed-off-by: Matt Lord <[email protected]>

go/mysql/binlog_event_mysql56_test.go

@@ -141,6 +141,12 @@ func TestMysql56DecodeTransactionPayload(t *testing.T) {
 		},
 	}
 
+	// Ensure that we can process events where the *uncompressed* size is
+	// larger than ZstdInMemoryDecompressorMaxSize. The *compressed* size
+	// of the payload in large_compressed_trx_payload.bin is 16KiB so we
+	// set the max to 1KiB to test this.
+	ZstdInMemoryDecompressorMaxSize = 1024 * 1024
+
 	for _, tc := range testCases {
 		memDecodingCnt := compressedTrxPayloadsInMem.Get()
 		streamDecodingCnt := compressedTrxPayloadsUsingStream.Get()