Apply CSS to the model name column

The model name is in the second column, so with this fix, I believe we can prevent the cell from expanding when a long model name is submitted.

src/display/css_html_js.py

@@ -39,8 +39,8 @@ custom_css = """
 }
 
 /* Limit the width of the first AutoEvalColumn so that names don't expand too much */
-table td:first-child,
-table th:first-child {
+#leaderboard-table td:nth-child(2),
+#leaderboard-table th:nth-child(2) {
     max-width: 400px;
     overflow: auto;
     white-space: nowrap;