Fix stylelint warnings in related_items_list.scss

This commit rearranges the styles in related_items_list
to adhere to stylelint's warnings. It also adds some
utility classes where applicable

app/assets/javascripts/vue_shared/components/issue/issue_milestone.vue

@@ -72,7 +72,7 @@ export default {
 <template>
   <div ref="milestoneDetails" class="issue-milestone-details">
     <icon :size="16" class="inline icon" name="clock" />
-    <span class="milestone-title">{{ milestone.title }}</span>
+    <span class="milestone-title d-inline-block">{{ milestone.title }}</span>
     <gl-tooltip :target="() => $refs.milestoneDetails" placement="bottom" class="js-item-milestone">
       <span class="bold">{{ __('Milestone') }}</span> <br />
       <span>{{ milestone.title }}</span> <br />

app/assets/javascripts/vue_shared/components/issue/related_issuable_item.vue

@@ -81,8 +81,11 @@ export default {
             :title="stateTitle"
             :aria-label="state"
             data-html="true"
+            class="d-xl-none"
           />
-          <span v-tooltip :title="itemPath" class="path-id-text">{{ itemPath }}</span>
+          <span v-tooltip :title="itemPath" class="path-id-text d-inline-block">{{
+            itemPath
+          }}</span>
           {{ pathIdSeparator }}{{ itemId }}
         </div>
         <div class="item-meta-child d-flex align-items-center">