tests: Do not invoke gtester-report

This results in:

  Traceback (most recent call last):
    File "/usr/bin/gtester-report", line 492, in <module>
      main()
    File "/usr/bin/gtester-report", line 486, in main
      HTMLReportWriter(rr.get_info(), rr.binary_list()).printout()
    File "/usr/bin/gtester-report", line 350, in printout
      self.handle_info ()
    File "/usr/bin/gtester-report", line 244, in handle_info
      self.oprint ('<h3>Package: %(package)s, version: \
                    %(version)s</h3>\n' % self.info)
  KeyError: 'package'

$ python --version
Python 2.7.3
$ gtester -v
gtester version 2.32.4
$ gtester-report -v
gtester-report (GLib utils) version 0.0-uninstalled.

See also:
* https://bugzilla.gnome.org/show_bug.cgi?id=668035

Signed-off-by: Toni Gundogdu <legatvs@gmail.com>