avocado.plugins.test_list: Display multiple tests.

When a class has multiple tests, display each test.

Example:

INSTRUMENTED examples/tests/gdbtest.py:GdbTest.test_connect_multiple_clients
Signed-off-by: NRudá Moura <rmoura@redhat.com>

avocado/plugins/test_list.py

@@ -129,6 +129,7 @@ class TestList(plugin.Plugin):
             else:
                 if issubclass(cls, test.Test):
                     stats['instrumented'] += 1
+                    id_label = params['name']
                     type_label = self.term_support.healthy_str('INSTRUMENTED')
 
             test_matrix.append((type_label, id_label))