readme: seq_file.sh -> seq_file_single_open.sh

Author: cirosantilli

README.adoc

@@ -7751,7 +7751,7 @@ Bibliography:
 If you have the entire read output upfront, `single_open` is an even more convenient version of <<seq-file>>:
 
 ....
-./seq_file.sh
+./seq_file_single_open.sh
 echo $?
 ....