Removed unused trigram index on users. Fixed users_fts_index usage.

priv/repo/migrations/20200708193702_drop_user_trigram_index.exs

@@ -0,0 +1,18 @@
+defmodule Pleroma.Repo.Migrations.DropUserTrigramIndex do
+  @moduledoc "Drops unused trigram index on `users` (FTS index is being used instead)"
+
+  use Ecto.Migration
+
+  def up do
+    drop_if_exists(index(:users, [], name: :users_trigram_index))
+  end
+
+  def down do
+    create_if_not_exists(
+      index(:users, ["(trim(nickname || ' ' || coalesce(name, ''))) gist_trgm_ops"],
+        name: :users_trigram_index,
+        using: :gist
+      )
+    )
+  end
+end