Strip only trailing line ender from log lines produced by actions. (#4852)

Stripping both leading and trailing spaces will alter the formatting of the logs produced by actions.
This changes the stripping only to trailing new line or return character.

Author: rabbah

common/scala/src/main/scala/org/apache/openwhisk/core/containerpool/logging/DockerToActivationLogStore.scala

@@ -39,7 +39,7 @@ import spray.json._
  * Represents a single log line as read from a docker log
  */
 protected[core] case class LogLine(time: String, stream: String, log: String) {
-  def toFormattedString = f"$time%-30s $stream: ${log.trim}"
+  def toFormattedString = f"$time%-30s $stream: ${log.stripLineEnd}"
 }
 
 protected[core] object LogLine extends DefaultJsonProtocol {