BAU: Fix imports for test file

The tests weren't able to run locally without the imports despite
running successfully in GHA

Author: alhcomer

src/handlers/tests/internal-server-error-handler.test.ts

@@ -1,6 +1,7 @@
 import { expect } from "chai";
+import { describe } from "mocha";
 import type { NextFunction, Request, Response } from "express";
-import sinon from "sinon";
+import { sinon } from "../../../test/utils/test-utils.js";
 import { ERROR_MESSAGES, HTTP_STATUS_CODES } from "../../app.constants.js";
 import { serverErrorHandler } from "../internal-server-error-handler.js";
 describe("serverErrorHandler", () => {