tx driver connection pool leak

The tx driver conn pooling leaks, as

https://github.com/jbosstm/narayana/blob/a66d5bd3ebfa96ab7e4142f28960a99b941a30e7/ArjunaJTA/jdbc/classes/com/arjuna/ats/internal/jdbc/ConnectionManager.java#L124

if (!con.inUse() && isSameConnection(dbUrl, user, passwd, dynamic, xaDataSource, con.connectionControl()))

is ineffective at permitting connection reuse, as isSameConnection equality requires that

https://github.com/jbosstm/narayana/blob/a66d5bd3ebfa96ab7e4142f28960a99b941a30e7/ArjunaJTA/jdbc/classes/com/arjuna/ats/internal/jdbc/ConnectionManager.java#L181

dynamic.equals(connControl.dynamicClass())

which does not hold as BaseTransactionalDriverXAConnection.dynamicClass() is not overridden by DirectRecoverableConnection.

proposed fix: make BaseTransactionalDriverXAConnection.dynamicClass() non-final, add

@Override
public final String dynamicClass()

{ return _dynamic; }

to DirectRecoverableConnection. Add test coverage.