Add more verbosity for Common.retry function

Currently it is not clear why sometimes failed body of
retry block, so let's add message with exception message.

Change-Id: I7ba56063be197f42d846485b129941de069da597
Related-Prod: PROD-26381
(cherry picked from commit 900a3afa6e1d75df702a1a5474ed51e3876e4433)
diff --git a/src/com/mirantis/mk/Common.groovy b/src/com/mirantis/mk/Common.groovy
index 4922505..901b842 100644
--- a/src/com/mirantis/mk/Common.groovy
+++ b/src/com/mirantis/mk/Common.groovy
@@ -534,11 +534,11 @@
 
 def retry(int times = 5, int delay = 0, Closure body) {
     int retries = 0
-    def exceptions = []
     while (retries++ < times) {
         try {
             return body.call()
         } catch (e) {
+            errorMsg(e.toString())
             sleep(delay)
         }
     }