fix checking in actionLimitTest (#1857)

diff --git a/tests/src/whisk/core/limits/ActionLimitsTests.scala b/tests/src/whisk/core/limits/ActionLimitsTests.scala
index 79e932f..d407103 100644
--- a/tests/src/whisk/core/limits/ActionLimitsTests.scala
+++ b/tests/src/whisk/core/limits/ActionLimitsTests.scala
@@ -229,8 +229,7 @@
                     n.toInt should be >= minExpectedOpenFiles
 
                     activation.logs.getOrElse(List()).filter {
-                        // drop time stamp and stdout/err markers
-                        _.split(" ").drop(2).mkString(" ").startsWith("ERROR: opened files = ")
+                        _.contains("ERROR: opened files = ")
                     }.length shouldBe 1
             }
     }