AudioVideoValidator: Fix embedded attachment requirements

lib/pleroma/web/activity_pub/object_validators/audio_video_validator.ex

@@ -104,14 +104,14 @@ def changeset(struct, data) do
 
     struct
     |> cast(data, __schema__(:fields) -- [:attachment, :tag])
-    |> cast_embed(:attachment)
+    |> cast_embed(:attachment, required: true)
     |> cast_embed(:tag)
   end
 
   defp validate_data(data_cng) do
     data_cng
     |> validate_inclusion(:type, ["Audio", "Video"])
-    |> validate_required([:id, :actor, :attributedTo, :type, :context, :attachment])
+    |> validate_required([:id, :actor, :attributedTo, :type, :context])
     |> CommonValidations.validate_any_presence([:cc, :to])
     |> CommonValidations.validate_fields_match([:actor, :attributedTo])
     |> CommonValidations.validate_actor_presence()

test/pleroma/object/fetcher_test.exs

@@ -166,7 +166,7 @@ test "it resets instance reachability on successful fetch" do
       Instances.set_consistently_unreachable(id)
       refute Instances.reachable?(id)
 
-      {:ok, object} =
+      {:ok, _object} =
         Fetcher.fetch_object_from_id("http://mastodon.example.org/@admin/99541947525187367")
 
       assert Instances.reachable?(id)