change BootStrapContextService dependency on WorkManagerService from OPTIONAL to REQUIRED

In connector/src/main/java/org/jboss/as/connector/subsystems/jca/BootstrapContextAdd.java the dependecy type specified is OPTIONAL, which deprecated and discouraged.
In addition, this dependency may cause failures during the boot if bootstrap context is added to management model before the workmanager (which is what happens during the testing of the filesystem tree based model persistence where the order of resources is not generally enforced).
Changing the dependency type to REQUIRED fixes the issue.