Remove type assertion in getAsciiArt test

  assertEquals(results, EXPECTED_GRAY_IDX);

});

Deno.test("getAsciiArt - Darkest Letter", () => {

Deno.test("getAsciiArt - Darkest Letter", async () => {

  // Create black and white 1x1 images using Jimp constructor

  const blackImage = new Jimp({ width: 1, height: 1, color: 0x000000ff });

  const blackImageBuffer = await blackImage.getBuffer("image/webp");

  const blackResult = getAsciiArt(

    blackImage as unknown as Parameters<typeof getAsciiArt>[0],

    await Jimp.read(blackImageBuffer),

    1,

    true,

  );

  assertEquals(blackResult.includes("█"), true);

  assertEquals(blackResult, "█");

});

Deno.test("getAsciiArt - Brightest Letter", async () => {

  // Create black and white 1x1 images using Jimp constructor

  const whiteImage = new Jimp({ width: 1, height: 1, color: 0xffffffff });

  const whiteImageBuffer = await whiteImage.getBuffer("image/webp");

  const whiteResult = getAsciiArt(

    await Jimp.read(whiteImageBuffer),

    1,

    true,

  );

  assertEquals(whiteResult, " ");

});