getFirstMinion should return minion id

* Minion id may not be in FQDN format
* pipeline-library should not use any wildcards (*) for minion
  targeting
* Unexpected minions may be filtered for result of this function
  For example:
    getFirstMinion returns 'ctl01'
    execution of salt.getReturnValues with 'ctl01*' will also filter
    'ctl0100'

Change-Id: Ia2b3460aeabc928f7cfa7d01a4dacb91e36c9e9d
Related-PROD: PROD-22709
diff --git a/src/com/mirantis/mk/Salt.groovy b/src/com/mirantis/mk/Salt.groovy
index eb7b168..e2f4189 100644
--- a/src/com/mirantis/mk/Salt.groovy
+++ b/src/com/mirantis/mk/Salt.groovy
@@ -599,7 +599,7 @@
  */
 def getFirstMinion(saltId, target) {
     def minionsSorted = getMinionsSorted(saltId, target)
-    return minionsSorted[0].split("\\.")[0]
+    return minionsSorted[0]
 }
 
 /**