Somehow fixed the repo insert [skip-ci]

lib/pleroma/web/thread_mute.ex

@@ -14,7 +14,8 @@ defmodule Pleroma.Web.ThreadMute do
 
   def add_mute(user, id) do
     %{data: %{"context" => context}} = Activity.get_by_id(id)
-    Repo.insert(%Pleroma.Web.ThreadMute{}, %{user_id: user.id, context: context})
+    mute = %Pleroma.Web.ThreadMute{user_id: user.id, context: context}
+    Repo.insert(mute)
   end
 
   def remove_mute(user, id) do

priv/repo/migrations/20190205114625_create_thread_mutes.exs

@@ -3,10 +3,10 @@ defmodule Pleroma.Repo.Migrations.CreateThreadMutes do
 
   def change do
     create table(:thread_mutes) do
-      add :user, references(:users, type: :uuid, on_delete: :delete_all)
+      add :user_id, references(:users, type: :uuid, on_delete: :delete_all)
       add :context, :string
     end
     
-    create index(:thread_mutes, [:user])
+    create index(:thread_mutes, [:user_id])
   end
 end