Fixed Jersey build on JDK 7.

- Previous commit (JERSEY-2206 + JERSEY-2123) introduced a reference to Guava component in the test code that does not have Guava dependency declared.
- The fix removes the need for the Guava dependency. 

Change-Id: If44be0102e613fb01bccc8b4412a09c59b137f19
Signed-off-by: Marek Potociar <marek.potociar@oracle.com>