Fix failing unit test due to sqlalchemy object not initialized

Use duck typing check instead of isinstance.
Inside the test I can't instantiate a proper type object with
all the needed mocked properties.

packit_service/models.py

@@ -162,10 +162,10 @@ def get_submitted_time_from_model(
 ) -> datetime:
     # TODO: unify `submitted_name` (or better -> create for both models `task_accepted_time`)
     # to delete this mess plz
-    if isinstance(model, CoprBuildTargetModel):
-        return model.build_submitted_time
-
-    return model.submitted_time
+    try:
+        return model.build_submitted_time  # type: ignore[union-attr]
+    except AttributeError:
+        return model.submitted_time  # type: ignore[union-attr]
 
 
 @overload

tests/unit/events/conftest.py

@@ -26,17 +26,14 @@ def mock_config():
 def tf_models():
     time = datetime(2000, 4, 28, 14, 9, 33, 860293)
     latest_time = datetime.utcnow()
-    fake_tf = flexmock(pipeline_id="1", submitted_time=time, target="target")
-    flexmock(TFTTestRunTargetModel).new_instances(fake_tf)
-    tf = TFTTestRunTargetModel()
-    tf.__class__ = TFTTestRunTargetModel
-
-    another_fake_tf = flexmock(
-        pipeline_id="2",
-        submitted_time=latest_time,
-        target="target",
-    )
-    flexmock(TFTTestRunTargetModel).new_instances(another_fake_tf)
-    another_tf = TFTTestRunTargetModel()
-    another_tf.__class__ = TFTTestRunTargetModel
+    tf = flexmock(TFTTestRunTargetModel).new_instances().mock()
+    tf.pipeline_id = "1"
+    tf.submitted_time = time
+    tf.target = "target"
+
+    another_tf = flexmock(TFTTestRunTargetModel).new_instances().mock()
+    another_tf.pipeline_id = "2"
+    another_tf.submitted_time = latest_time
+    another_tf.target = "target"
+
     yield [tf, another_tf]

tests/unit/events/test_copr.py

@@ -32,19 +32,15 @@ def copr_build_results_end():
 def copr_models():
     time = datetime(2000, 4, 28, 14, 9, 33, 860293)
     latest_time = datetime.utcnow()
-    fake_copr = flexmock(build_id="1", build_submitted_time=time, target="target")
-    flexmock(CoprBuildTargetModel).new_instances(fake_copr)
-    copr = CoprBuildTargetModel()
-    copr.__class__ = CoprBuildTargetModel
-
-    another_fake_copr = flexmock(
-        build_id="2",
-        build_submitted_time=latest_time,
-        target="target",
-    )
-    flexmock(CoprBuildTargetModel).new_instances(another_fake_copr)
-    another_copr = CoprBuildTargetModel()
-    another_copr.__class__ = CoprBuildTargetModel
+    copr = flexmock(CoprBuildTargetModel).new_instances().mock()
+    copr.build_id = "1"
+    copr.build_submitted_time = time
+    copr.target = "target"
+
+    another_copr = flexmock(CoprBuildTargetModel).new_instances().mock()
+    another_copr.build_id = "2"
+    another_copr.build_submitted_time = latest_time
+    another_copr.target = "target"
 
     yield [copr, another_copr]