fix: use timestamp with timezone for signing_keys

Signed-off-by: Erik Larsson <erik.larsson@schibsted.com>

.changeset/hungry-jars-knock.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-auth-backend': minor
+---
+
+Fixes timezone bug for auth signing keys

plugins/auth-backend/migrations/20210326100300_timestamptz.js

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// @ts-check
+
+/**
+ * @param {import('knex').Knex} knex
+ */
+exports.up = function (knex, Promise) {
+  return knex.schema.alterTable('signing_keys', function (t) {
+    t.timestamp('created_at', { useTz: true, precision: 0 })
+      .notNullable()
+      .defaultTo(knex.fn.now())
+      .comment('The creation time of the key')
+      .alter();
+  });
+};
+
+exports.down = function (knex, Promise) {
+  return knex.schema.alterTable('signing_keys', function (t) {
+    t.timestamp('created_at', { useTz: false, precision: 0 })
+      .notNullable()
+      .defaultTo(knex.fn.now())
+      .comment('The creation time of the key')
+      .alter();
+  });
+};