templates: fetch fixed size of members' avatar (#5755)

Co-authored-by: Joe Chen <[email protected]>

templates/org/member/members.tmpl

@@ -14,7 +14,7 @@
 			{{range .Members}}
 				<div class="item ui grid">
 					<div class="ui one wide column">
-						<img class="ui avatar" src="{{.RelAvatarLink}}?s=48">
+						<img class="ui avatar" src="{{AppendAvatarSize .RelAvatarLink 48}}">
 					</div>
 					<div class="ui three wide column">
 						<div class="meta"><a href="{{.HomeLink}}">{{.Name}}</a></div>