hello: print Jenkins URL

This makes it easier to debug when testing with multiple Jenkins master
environments.

rhcephpkg/hello.py

@@ -32,3 +32,4 @@ def _run(self):
         name = data['fullName']  # Our Jenkins instance gets this from LDAP
         jenkins_version = jenkins.get_version()
         print('Hello %s from Jenkins %s' % (name, jenkins_version))
+        print('Logged in to %s' % jenkins.url)

rhcephpkg/tests/test_hello.py

@@ -26,4 +26,6 @@ def test_success(self, monkeypatch, capsys):
         hello = Hello([])
         hello._run()
         out, _ = capsys.readouterr()
-        assert out == "Hello Ken from Jenkins 1.5\n"
+        expected = "Hello Ken from Jenkins 1.5\n" \
+                   "Logged in to https://ceph-jenkins.example.com/\n"
+        assert out == expected