make sure status images always display for a list of builds

src/root/static/css/hydra.css

@@ -114,4 +114,8 @@ td.nowrap {
 
 span.keep-whitespace {
     white-space: pre-wrap;
-}
+}
+
+.build-status {
+    max-width: none; /* don't apply responsive design to status images */
+}