Only show first 8 characters of git commit hash on about page

frontend/src/app/components/about/about.component.html

@@ -5,7 +5,7 @@
     <br /><br />
 
     <div class="text-small text-center">
-      Git commit: {{ gitCommit$ | async }}
+      v2.0-SNAPSHOT ({{ gitCommit$ | async }})
     </div>
 
     <br>