Update to Phoenix 1.6 and chase dependencies

Also bump minimum Elixir to 1.11

priv/repo/migrations/20221103014611_create_oban_peers.exs

@@ -0,0 +1,7 @@
+defmodule Pleroma.Repo.Migrations.CreateObanPeers do
+  use Ecto.Migration
+
+  def up, do: Oban.Migrations.up(version: 11)
+
+  def down, do: Oban.Migrations.down(version: 11)
+end

priv/repo/migrations/20221103014728_swap_primary_oban_indexes.exs

@@ -0,0 +1,26 @@
+defmodule Pleroma.Repo.Migrations.SwapPrimaryObanIndexes do
+  use Ecto.Migration
+
+  @disable_ddl_transaction true
+  @disable_migration_lock true
+
+  def change do
+    create_if_not_exists(
+      index(
+        :oban_jobs,
+        [:state, :queue, :priority, :scheduled_at, :id],
+        concurrently: true,
+        prefix: "public"
+      )
+    )
+
+    drop_if_exists(
+      index(
+        :oban_jobs,
+        [:queue, :state, :priority, :scheduled_at, :id],
+        concurrently: true,
+        prefix: "public"
+      )
+    )
+  end
+end