ansible: update git-wrapper for z/OS (#3323)

Tag `.git/config` as iso8859-1 to prevent it being interpreted as
EBCDIC.

Refs: #3320 (comment)

Author: richardlau

ansible/roles/jenkins-worker/templates/git-wrapper.j2

@@ -5,6 +5,10 @@ export _TAG_REDIR_ERR=txt
 export _TAG_REDIR_IN=txt
 export _TAG_REDIR_OUT=txt
 
+if [[ $WORKSPACE != "" ]]; then
+  chtag -t -c iso8859-1 "$WORKSPACE/.git/config"
+fi
+
 if [[ $1 == "rev-parse" ]]; then
   {{ git_cmd }} "$@" | cat
 elif [[ $1 == "whatchanged" ]]; then