refactor: Use fixtures for getUser graphQL tests

packages/backend/test/fixtures/role.ts

@@ -0,0 +1,15 @@
+type RoleParams = {
+  name?: string;
+  key?: string;
+};
+
+const createRole = async (params: RoleParams = {}) => {
+  params.name = params?.name || 'Viewer';
+  params.key = params?.key || 'viewer';
+
+  const [role] = await knex.table('roles').insert(params).returning('*');
+
+  return role;
+};
+
+export default createRole;