feat: make Tailwind migrations a 2-steps process

What does this MR do?

feat: make Tailwind migrations a 2-steps process

Updates the Tailwind migration script so that Prettier can be run after the migrations. This gives us a chance to commit the changes right after the migrations and before the CSS utils get re-ordered, which might make diffs confusing.

How to test this?

• Ensure you have some files with unordered legacy utils. For example, apply the following patch to src/components/base/card/card.vue:

  diff --git a/src/components/base/card/card.vue b/src/components/base/card/card.vue
  index f0a3d9ec7..8d8142fb6 100644
  --- a/src/components/base/card/card.vue
  +++ b/src/components/base/card/card.vue
  @@ -33,11 +33,7 @@ export default {
   
   <template>
     <div class="gl-card">
  -    <div
  -      v-if="$scopedSlots.header"
  -      class="gl-card-header gl-flex sm:gl-hidden"
  -      :class="headerClass"
  -    >
  +    <div v-if="$scopedSlots.header" class="gl-card-header gl-sm-display-none gl-display-flex" :class="headerClass">
         <!-- @slot The card's header content. -->
         <slot name="header"></slot>
       </div>

• Run the script against some directories that need migrating and that contain frontend files. Eg:

  bin/migrate_custom_utils_to_tw.mjs --directories src/components/base/card/

  • The script should hang once the utils have been migrated, at which point you can commit the changes.

• Resume the script's execution by typing Enter

  • The files should now be prettified.

Screenshots or screen recordings

2_steps_script

Integration merge requests

• GitLab: mr_url
• CustomersDot: mr_url
• Status Page: mr_url

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