patch 9.1.0464: no whitespace padding in commentstring option in ftplugins

Problem:  no whitespace padding in commentstring option in ftplugins
Solution: Change default to include whitespace padding, update
          existing filetype plugins with the new default value
          (Riley Bruins)

closes: #14843

Signed-off-by: Riley Bruins <ribru17@hotmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/ftplugin/groovy.vim b/runtime/ftplugin/groovy.vim
index cc7d6e3..a2e2b2f 100644
--- a/runtime/ftplugin/groovy.vim
+++ b/runtime/ftplugin/groovy.vim
@@ -2,6 +2,7 @@
 " Language:	groovy
 " Maintainer:	Justin M. Keyes <justinkz@gmail.com>
 " Last Change:	2016 May 22
+" 		2024 May 24 by Riley Bruins <ribru17@gmail.com> ('commentstring')
 
 if exists('b:did_ftplugin')
   finish
@@ -13,7 +14,7 @@
 
 let b:undo_ftplugin = 'setlocal commentstring<'
 
-setlocal commentstring=//%s
+setlocal commentstring=//\ %s
 
 let &cpo = s:cpo_save
 unlet s:cpo_save