dokuwiki: Sanitise update.sh

dokuwiki/templates/update.sh.j2

 #!/bin/sh
 
-cwd=$PWD
-
 {% for dw in dokuwiki %}
-cd {{ dw.path }}
-curl -s https://update.dokuwiki.org/check/$(grep updateVersion doku.php | sed -E 's/\$updateVersion = "(.*)";/\1/g')
+curl -s https://update.dokuwiki.org/check/"$(sed -n -E '/updateVersion/ { s/\$updateVersion = "(.*)";/\1/g; p; q }' "{{ dw.path }}"/doku.php)"
 {% endfor %}
-
-cd ${cwd}