Namespace markdown area styles on new epic form

ee/app/assets/javascripts/epic/components/epic_form.vue

@@ -118,7 +118,7 @@ export default {
     <h3 class="page-title gl-border-b-solid gl-border-b-gray-100 gl-border-b-1 gl-pb-5 gl-mb-6">
       {{ __('New Epic') }}
     </h3>
-    <gl-form class="common-note-form" @submit="save">
+    <gl-form class="common-note-form new-epic-form" @submit="save">
       <gl-form-group :label="__('Title')" label-for="epic-title">
         <gl-form-input
           id="epic-title"

ee/app/assets/stylesheets/pages/epics.scss

@@ -82,7 +82,7 @@
   color: $gl-text-color-tertiary;
 }
 
-.md-area.gfm-form {
+.new-epic-form .md-area.gfm-form {
   @include gl-rounded-base;
   @include gl-border-none;
   @include gl-inset-border-1-gray-400;