Fix how concurrency is set

package.json

@@ -108,7 +108,7 @@
         "c9.ide.save": "#5118b30230",
         "c9.ide.scm": "#bd5ca2557c",
         "c9.ide.terminal.monitor": "#35afa7f97f",
-        "c9.ide.test": "#b84f9caa19",
+        "c9.ide.test": "#4aba510ed9",
         "c9.ide.test.mocha": "#7844e1dc83",
         "c9.ide.theme.flat": "#92cda0fb40",
         "c9.ide.threewaymerge": "#229382aa0b",