[Improve][Connector-V2][FTP] delete duplicated code (#7915)

Author: zhangshenghang

Diff for: seatunnel-e2e/seatunnel-connector-v2-e2e/connector-file-ftp-e2e/src/test/java/org/apache/seatunnel/e2e/connector/file/ftp/FtpFileIT.java

@@ -94,7 +94,6 @@ public void startUp() throws Exception {
         int passiveEndPort = 30004;
         ftpContainer =
                 new GenericContainer<>(FTP_IMAGE)
-                        .withExposedPorts(FTP_PORT)
                         .withNetwork(NETWORK)
                         .withExposedPorts(FTP_PORT)
                         .withExposedPorts(