(doc) Removes Githack from Recommended Icon CDNs

Githack previously did cache icon files as we expect, but the functionality has now been turned off (see: neoascetic/rawgithack#82).

This commit removes Githack from the recommended icon CDNs on our package creation page.

Author: JPRuskin

src/content/docs/en-us/create/create-packages.mdx

@@ -400,7 +400,7 @@ For Chocolatey, internationalization and localization of packages is very import
 If there is an icon which is suitable for your package, you can specify it in the `<iconUrl>` tag in the nuspec. But there are a few things you should consider:
 
 * **Avoid hotlinking icons from sites where you don’t have control over the file.** If you have a packages repository (recommended), use your own copy of the icon and put it there.
-* **Use a static CDN for icon URLs that permits you to serve files hosted in a repository on GitHub.** Some CDN services cache files permanently and it's therefore best to use a specific tag or commit URL, not a branch URL. While we don't make any recommendations about specific services, the more popular ones used by maintainers are [jsDelivr](https://www.jsdelivr.com/), [Statically](https://statically.io/) and [Githack](https://raw.githack.com/).
+* **Use a static CDN for icon URLs that permits you to serve files hosted in a repository on GitHub.** Some CDN services cache files permanently and it's therefore best to use a specific tag or commit URL, not a branch URL. While we don't make any recommendations about specific services, some popular ones used by maintainers are [jsDelivr](https://www.jsdelivr.com/) and [Statically](https://statically.io/).
 * **Avoid using GitHub raw links** (`https://raw.githubusercontent.com/...`). They are not intended to be used as CDN.
 * **Use the software’s icon if one is available, not the logo.** This blog post explains the difference between logos and icons: http://blog.designcrowd.com/article/353/differences-between-logos-and-icons. If the software of your package doesn’t have an icon, but a logo with text and an image, you can extract the image with your favorite image editor and use that as package icon. An example is [MySQL’s dolphin](https://community.chocolatey.org/packages/mysql).
 * **Use package icons with at least 128 pixels in width or height** if available. However, avoid very high resolutions, because this would only unnecessarily increase the page load time. If there are only icons with less than 128 pixels available, choose the icon with the highest resolution you can find without upscaling it. Don’t use low resolution favicons as package icons.