[etcd] fix make-ssl-etcd.sh.j2; move pem files only if any new certs exist (#9974)

roles/etcd/templates/make-ssl-etcd.sh.j2

@@ -100,4 +100,6 @@ if [ -e "$SSLDIR/ca-key.pem" ]; then
     rm -f ca.pem ca-key.pem
 fi
 
-mv *.pem ${SSLDIR}/
+if [ -n "$(ls -A *.pem)" ]; then
+    mv *.pem ${SSLDIR}/
+fi