Added side margin to Clone button

On the Snippet view with "Clone" button visible, there's not enough
right margin to comply with Pajamas. This MR fixes this issue.

app/assets/javascripts/snippets/components/snippet_blob_view.vue

@@ -75,6 +75,7 @@ export default {
         <template #actions>
           <clone-dropdown-button
             v-if="canBeCloned"
+            class="mr-2"
             :ssh-link="snippet.sshUrlToRepo"
             :http-link="snippet.httpUrlToRepo"
           />

changelogs/unreleased/dmishunov-clone-btn-margin.yml

+---
+title: Added right margin to Clone Snippet button
+merge_request: 30471
+author:
+type: fixed