Apply suggestions from code review

Co-authored-by: Norwin <[email protected]>

Author: zeripath

templates/repo/diff/conversation.tmpl

@@ -28,8 +28,12 @@
 		</div>
 		<div class="df je ac fw mt-3">
 			<div class="ui buttons mr-2">
-				<button class="ui icon tiny basic button previous-conversation">{{$.i18n.Tr "repo.issues.previous"}}</button>
-				<button class="ui icon tiny basic button next-conversation">{{$.i18n.Tr "repo.issues.next"}}</button>
+				<button class="ui icon tiny basic button previous-conversation">
+				  {{svg "octicon-arrow-up"}} {{$.i18n.Tr "repo.issues.previous"}}
+				</button>
+				<button class="ui icon tiny basic button next-conversation">
+				  {{svg "octicon-arrow-down"}} {{$.i18n.Tr "repo.issues.next"}}
+				</button>
 			</div>
 			{{if and $.CanMarkConversation $isNotPending}}
 				<button class="ui icon tiny basic button resolve-conversation" data-origin="diff" data-action="{{if not $resolved}}Resolve{{else}}UnResolve{{end}}" data-comment-id="{{(index .comments 0).ID}}" data-update-url="{{$.RepoLink}}/issues/resolve_conversation">