Add missing background center on public profile headers (#3340)

app/javascript/styles/accounts.scss

@@ -1,6 +1,7 @@
 .card {
   background: $ui-base-color;
   background-size: cover;
+  background-position: center;
   padding: 60px 0;
   padding-bottom: 0;
   border-radius: 4px 4px 0 0;