Adding Unit tests for PersonSearchAdviser Class

PersonSearchAdviser class has some functions which are not covered with unit tests yet. So it should be covered with the unit tests to increase the test coverage. 

PersonSearchAdviser : https://github.com/openmrs/openmrs-module-locationbasedaccess/blob/master/api/src/main/java/org/openmrs/module/locationbasedaccess/aop/PersonSearchAdviser.java