Add missing copyright headers

Author: ZedLi

addons/api/addon/services/db.js

@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) HashiCorp, Inc.
+ * SPDX-License-Identifier: BUSL-1.1
+ */
+
 import Service, { service } from '@ember/service';
 import { modelMapping } from 'api/services/sqlite';
 import { assert } from '@ember/debug';

addons/api/app/services/db.js

@@ -1 +1,6 @@
+/**
+ * Copyright (c) HashiCorp, Inc.
+ * SPDX-License-Identifier: BUSL-1.1
+ */
+
 export { default } from 'api/services/db';

addons/api/tests/unit/services/db-test.js

@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) HashiCorp, Inc.
+ * SPDX-License-Identifier: BUSL-1.1
+ */
+
 import { module, test } from 'qunit';
 import { setupTest } from 'dummy/tests/helpers';