Move EE differences for `app/assets/javascripts/pages/milestones/shared/components/promote_milestone_modal.vue`

The file `` has differences between CE and EE.

Diferences

diff --git a/home/yorickpeterse/Projects/gitlab/gdk-ce/gitlab/app/assets/javascripts/pages/milestones/shared/components/promote_milestone_modal.vue b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/app/assets/javascripts/pages/milestones/shared/components/promote_milestone_modal.vue
index a79ef07f1c5..42124c63885 100644
--- a/home/yorickpeterse/Projects/gitlab/gdk-ce/gitlab/app/assets/javascripts/pages/milestones/shared/components/promote_milestone_modal.vue
+++ b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/app/assets/javascripts/pages/milestones/shared/components/promote_milestone_modal.vue
@@ -31,11 +31,26 @@ export default {
       });
     },
     text() {
+      const milestonePromotion = sprintf(
+        s__(`Milestones|Promoting %{milestone} will make it available for all projects inside %{groupName}.
+          Existing project milestones with the same name will be merged. `),
+        {
+          milestone: this.milestoneTitle,
+          groupName: this.groupName,
+        },
+      );
+      const finalWarning = s__('Milestones|This action cannot be reversed.');
+
       return sprintf(
-        s__(`Milestones|Promoting %{milestoneTitle} will make it available for all projects inside %{groupName}.
-        Existing project milestones with the same title will be merged.
-        This action cannot be reversed.`),
-        { milestoneTitle: this.milestoneTitle, groupName: this.groupName },
+        s__(
+          `Milestones|<p>%{milestonePromotion}</p>
+          %{finalWarning}`,
+        ),
+        {
+          milestonePromotion,
+          finalWarning,
+        },
+        false,
       );
     },
   },
@@ -72,6 +87,6 @@ export default {
     <template slot="title">
       {{ title }}
     </template>
-    {{ text }}
+    <div v-html="text"></div>
   </gl-modal>
 </template>

What needs to be done

1. Create a EE mixin & CE counterpart & use ee_else_ce to import it