* Remove usage of removed `org.springframework.util.SocketUtils` in favor of OS-selected port * Migrate mail tests to Greenmail instead of already obsolete (and soon to be removed) `org.springframework.integration.test.mail.TestMailServer`
* Remove usage of removed `org.springframework.util.SocketUtils` in favor of OS-selected port * Migrate mail tests to Greenmail instead of already obsolete (and soon to be removed) `org.springframework.integration.test.mail.TestMailServer`