Attempt fix for DynamicToyMySqlEntityTest int test

Because the start script being nohupped and backgrounded, it seems that the lifecycle is allowing a mere 5 seconds for the MySQL process to start in the background, initialise itself and become ready for service. This is not quite enough, and could be the reason for the intermittent Jenkins failures in this test. Increase the wait to 30 seconds.
Revert "Attempt fix for DynamicToyMySqlEntityTest int test"

This reverts commit ab1f99b8e26d5d9faa42400e387bcc4733d4c1c5.
Fix DynamicToyMySqlEntityTest intermittent fails

No need to background the server start command; it just makes things brittle if the server start takes more than 5 seconds (because that's when postStart checks that the service is running). Run it in foreground, and it will exit normally once the server is started.
Merge pull request #1145 from richardcloudsoft/fix/DynamicToyMySqlEntityTest

Attempt fix for DynamicToyMySqlEntityTest int test