Show "commit detail" link only when gitUrl is set

* See #34

layouts/posts/single.html

@@ -37,7 +37,7 @@ <h1>{{ .Title }}</h1>
 				{{- end }}
 				<p><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-file-text"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"></path><polyline points="14 2 14 8 20 8"></polyline><line x1="16" y1="13" x2="8" y2="13"></line><line x1="16" y1="17" x2="8" y2="17"></line><polyline points="10 9 9 9 8 9"></polyline></svg>{{ i18n "wordCount" . }}</p>
 				<p><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-calendar"><rect x="3" y="4" width="18" height="18" rx="2" ry="2"></rect><line x1="16" y1="2" x2="16" y2="6"></line><line x1="8" y1="2" x2="8" y2="6"></line><line x1="3" y1="10" x2="21" y2="10"></line></svg>{{ dateFormat .Site.Params.dateformNumTime .Date.Local }}</p>
-				{{- if .GitInfo }}
+				{{- if and .GitInfo .Site.Params.gitUrl }}
 				<p><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-git-commit"><circle cx="12" cy="12" r="4"></circle><line x1="1.05" y1="12" x2="7" y2="12"></line><line x1="17.01" y1="12" x2="22.96" y2="12"></line></svg><a href="{{ .Site.Params.gitUrl -}}{{ .GitInfo.Hash }}" target="_blank" rel="noopener">{{ .GitInfo.AbbreviatedHash }}</a> @ {{ dateFormat .Site.Params.dateformNum .GitInfo.AuthorDate.Local }}</p>
 				{{- end }}
 			</footer>