Revert of Enable strict coverage for step module

recipes/engine_tests/trigger.py

+# Copyright 2013 The LUCI Authors. All rights reserved.
+# Use of this source code is governed under the Apache License, Version 2.0
+# that can be found in the LICENSE file.
+
+from recipe_engine.recipe_api import Property
+
+DEPS = [
+    'properties',
+    'step',
+]
+
+PROPERTIES = {
+    'command': Property(default=None),
+}
+
+def RunSteps(api, command):
+  api.step(
+      'trigger some junk',
+      cmd=command,
+      trigger_specs=[{
+          'builder_name': 'triggered',
+          'buildbot_changes': [{
+              'when_timestamp': 1445412480,
+          }],
+      }])
+
+def GenTests(api):
+  yield api.test('basic')