Migrate translate utilities to Tailwind

What does this MR do and why?

Migrates gl-translate-x-n50 to -gl-translate-x-1/2 and gl-translate-y-n50 to -gl-translate-y-1/2.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

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How to set up and validate locally

1. -gl-translate-x-1/2

   1. Set your status to Busy.
   2. Navigate to your profile page.
   3. Observe that the Busy badge is properly positioned below your avatar.

2. -gl-translate-y-1/2

   1. Navigate to a Wiki page.
   2. Place the mouse cursor over a link in the right navbar.
   3. Observe that the + icon is properly positioned.

3. CSS-in-Js

   1. Run the following script to produce a diff for the CSS-in-Js config:

   git checkout master
   rm config/helpers/tailwind/css_in_js.js && yarn tailwindcss:build
   git add --force config/helpers/tailwind/css_in_js.js
   git checkout 456636-tailwind-translate
   rm config/helpers/tailwind/css_in_js.js && yarn tailwindcss:build
   git diff config/helpers/tailwind/css_in_js.js

   1. This should cause the translate-x-n50 and translate-y-n50 utils to be dropped from the config. translate-y-n100 is still there because it's used in GitLab UI.

   diff --git a/config/helpers/tailwind/css_in_js.js b/config/helpers/tailwind/css_in_js.js
   index 5acd7badd749..30ab0e1f8bad 100644
   --- a/config/helpers/tailwind/css_in_js.js
   +++ b/config/helpers/tailwind/css_in_js.js
   @@ -1,5 +1,5 @@
    /**
   - * The following 640 definitions need to be migrated to Tailwind.
   + * The following 638 definitions need to be migrated to Tailwind.
     * Let's do this! 🚀
     */
    module.exports = {
   @@ -699,8 +699,6 @@ module.exports = {
        'max-width': '82%',
      },
      '.text-truncate': { overflow: 'hidden', 'text-overflow': 'ellipsis', 'white-space': 'nowrap' },
   -  '.translate-x-n50': { transform: 'translateX(-50%)' },
   -  '.translate-y-n50': { transform: 'translateY(-50%)' },
      '.translate-y-n100': { transform: 'translateY(-100%)' },
      '.transition-property-stroke': { 'transition-property': 'stroke' },
      '.transition-property-stroke-opacity': { 'transition-property': 'stroke-opacity' },

Related to #456636 (closed)