deps: Require `nss-tools` for make's fasttest target
    
    Otherwise, tests fail with:
    ```
    E               FileNotFoundError: [Errno 2] No such file or directory: '/usr/bin/certutil'
    ...
    =================================== short test summary info ===================================
    FAILED test_ipapython/test_certdb.py::test_dbm_tmp - FileNotFoundError: [Errno 2] No such fi...
    FAILED test_ipapython/test_certdb.py::test_sql_tmp - FileNotFoundError: [Errno 2] No such fi...
    FAILED test_ipapython/test_certdb.py::test_convert_db - FileNotFoundError: [Errno 2] No such...
    FAILED test_ipapython/test_certdb.py::test_convert_db_nokey - FileNotFoundError: [Errno 2] N...
    FAILED test_ipapython/test_certdb.py::test_auto_db - FileNotFoundError: [Errno 2] No such fi...
    FAILED test_ipapython/test_certdb.py::test_delete_cert_and_key - FileNotFoundError: [Errno 2...
    FAILED test_ipapython/test_certdb.py::test_check_validity - FileNotFoundError: [Errno 2] No ...
    ...
    ```
    
    Signed-off-by: Stanislav Levin <slev@altlinux.org>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>