Run tests in %check
    
    Build and run the provided tests in %check. The locale needs to be
    overriden to C.UTF-8 to make the Qt4 tests pass due to an issue with
    Japanese character handling.
    
    It is possible to disable the tests by building with `--without test`
    (for example `fedpkg mockbuild --without test`).
    
    Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>