Selftests: add most example jobs as tests

So that the features they use, end up being tested as a whole.

Note: these may and should become irrelevant once we have complete Job
API feature coverage, but it should catch and avoid breakages for now.
Signed-off-by: NCleber Rosa <crosa@redhat.com>

selftests/jobs/example_nrunner

+../../examples/jobs/nrunner.py
\ No newline at end of file

selftests/jobs/example_passjob

+../../examples/jobs/passjob.py
\ No newline at end of file

selftests/jobs/example_passjob_cit_varianter

+../../examples/jobs/passjob_cit_varianter.py
\ No newline at end of file

selftests/jobs/example_passjob_html

+../../examples/jobs/passjob_html.py
\ No newline at end of file

selftests/jobs/example_sleepjob_dict_varianter

+../../examples/jobs/sleepjob_dict_varianter.py
\ No newline at end of file

selftests/jobs/example_sleepjob_json_varianter

+../../examples/jobs/sleepjob_json_varianter.py
\ No newline at end of file