Added a test case for addBook method. Successful with normal parameter passing as expected
Added another test case for method AddBook to test duplicate record entry. The test passed indicating code needs to be reviewed to disallow duplicate ISBN to be entered.
Added a third test case for method AddBook to test negative entry for Publication_Year and Price. The test passed indicating code needs to be reviewed to disallow negative values from being entered.
Added a test case for method findBook.  The test passed with normal parameter for ISBN = 10 which exist in the DB
Added another test case for method findBook to pull records with null entries. The test passed but code review is needed for better return message for null value search.
Added another test case for method findBook to pull records with null entries. The test passed but code review is needed for better return message for null value search.
Added a test case for method updateBook. The test passed with normal passed with normal parameters.
Revert "Added a test case for method updateBook. The test passed with normal passed with normal parameters."

This reverts commit dc4fd732afcd49f801a279c8dbb0c471104df3ef.
Added a test case for method updateBook.
Clean up and retest...
Added a test case for updateBook and passed with normal parameters