examples: fixed passjob.py with automatic case and added a custom case

Adding here some some possible use case of the current API. So far I
notice that we have two big cases: automatic job discovery vs
manual/custom job. I understand that there is room for improvements but
I would like to keep things consistent and intuitive here, because of
that this work is separating the logic behind the constructors and the
from_config() methods for both: Job() and TestSuite().
Signed-off-by: NBeraldo Leal <bleal@redhat.com>

examples/jobs/passjob.py

 #!/usr/bin/env python3
-
 import sys
 
 from avocado.core.job import Job
-from avocado.core.suite import TestSuite
 
-config = {'run.references': ['examples/tests/passtest.py:PassTest.test']}
+job_config = {'run.test_runner': 'nrunner',
+              'run.references': ['examples/tests/passtest.py:PassTest.test']}
+
+# Automatic helper method (Avocado will try to discovery things from config
+# dicts. Since there is magic here, we dont need to pass suite names or suites,
+# and test/task id will be prepend with the suite index (in this case 1 and 2)
 
-suite = TestSuite.from_config(config)
-with Job(config, [suite]) as j:
-    sys.exit(j.run())
+job = Job.from_config(job_config=job_config)
+job.setup()
+sys.exit(job.run())

examples/jobs/passjob_custom.py

+import sys
+
+from avocado.core.job import Job
+from avocado.core.suite import TestSuite
+
+job_config = {'run.test_runner': 'nrunner'}
+
+config1 = {'run.references': ['examples/tests/passtest.py:PassTest.test']}
+config2 = {'run.references': ['examples/tests/passtest.py:PassTest.test']}
+
+# Custom method (no discovery, no guess, no magic)
+# Since there is no magic, we need to pass a suite name, otherwise a uuid4 will
+# be used for suite.name. Also run.references will be ignored (Avocado will not
+# creating tests suites for you).
+
+suite1 = TestSuite(config=config1, tests=[], name='suite1')
+suite2 = TestSuite(config=config2, tests=[], name='suite2')
+
+with Job(job_config, [suite1, suite2]) as j:
+    sys.exit(j.run())