User: Move public_key from source_data to own field

priv/repo/migrations/20200401030751_users_add_public_key.exs

@@ -0,0 +1,17 @@
+defmodule Pleroma.Repo.Migrations.UsersAddPublicKey do
+  use Ecto.Migration
+
+  def up do
+    alter table(:users) do
+      add_if_not_exists(:public_key, :text)
+    end
+
+    execute("UPDATE users SET public_key = source_data->'publicKey'->>'publicKeyPem'")
+  end
+
+  def down do
+    alter table(:users) do
+      remove_if_exists(:public_key, :text)
+    end
+  end
+end