The `TEST-UNEXPECTED-FAIL | checks that docIds are unique and increasing | in chrome | Expected 9 to be less than 0` unit test failed in a recent test run in https://github.com/mozilla/pdf.js/pull/13837#issuecomment-890511627, but also locally once for me. Perhaps this goes wrong because the test depends on state that might be mutated if the tests are shuffled?

/cc @Snuffleupagus since this unit test was added in https://github.com/mozilla/pdf.js/pull/13813/commits/b18620ac0f196c6fa5a9e54a53fa6b915e19e843
promise2,
        promise3,
      ]);
      expect(pageLabels[0]).toEqual(["i", "ii", "iii", "1"]);
      expect(pageLabels[1]).toEqual(["Front Page1"]);
      expect(pageLabels[2]).toEqual(["1", "2"]);
      expect(pageLabels[3]).toEqual(["X3"]);
      await Promise.all([
        loadingTask0.destroy(),
        loadingTask1.destroy(),
        loadingTask2.destroy(),
        loadingTask3.destroy(),
      ]);
    });
    it("gets default page layout", async function () {
      const loadingTask = getDocument(
        buildGetDocumentParams("tracemonkey.pdf")
      );
      const pdfDoc = await loadingTask.promise;
      const pageLayout = await pdfDoc.getPageLayout();
      expect(pageLayout).toEqual("");
      await loadingTask.destroy();
    });
    it("gets non-default page layout", async function () {
      const pageLayout = await pdfDocument.getPageLayout();
      expect(pageLayout).toEqual("SinglePage");
    });
    it("gets default page mode", async function () {
      const loadingTask = getDocument(
        buildGetDocumentParams("tracemonkey.pdf")