Remove commit load branches and tags in wiki repo (#26304)

If click `load branches and tags`, you will get 500 error from backend,
as it is a wiki repo.

![image](https://github.com/go-gitea/gitea/assets/18380374/1eb2a68b-cc72-4607-a1d1-4f74f83623f6)

![image](https://github.com/go-gitea/gitea/assets/18380374/c385de25-0cfb-4084-9452-d7e9d27deea9)

Co-authored-by: Giteabot <teabot@gitea.io>

templates/repo/commit_load_branches_and_tags.tmpl

@@ -1,3 +1,4 @@
+{{if not .PageIsWiki}}
 <div class="branch-and-tag-area" data-text-default-branch-tooltip="{{.locale.Tr "repo.commit.contained_in_default_branch"}}">
 	<button class="ui button ellipsis-button load-branches-and-tags gt-mt-3" aria-expanded="false"
 		data-fetch-url="{{.RepoLink}}/commit/{{.CommitID}}/load-branches-and-tags"
@@ -16,3 +17,4 @@
 		</div>
 	</div>
 </div>
+{{end}}