runtime(bp): fix comment definition in filetype plugin (#14594)

I somehow messed up the previous patch, I think a copy-paste error when
creating the file.

Blueprint files have C and C++ style comments, not shell-like '#'
comments.

Signed-off-by: Bruno BELANYI <bruno@belanyi.fr>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/ftplugin/bp.vim b/runtime/ftplugin/bp.vim
index cb925cb..5ddebe5 100644
--- a/runtime/ftplugin/bp.vim
+++ b/runtime/ftplugin/bp.vim
@@ -1,14 +1,14 @@
 " Blueprint build system filetype plugin file
 " Language: Blueprint
 " Maintainer: Bruno BELANYI <bruno.vim@belanyi.fr>
-" Latest Revision: 2024-04-10
+" Latest Revision: 2024-04-19
 
 if exists("b:did_ftplugin")
   finish
 endif
 let b:did_ftplugin = 1
 
-setlocal comments=b:#
-setlocal commentstring=#\ %s
+setlocal comments=b://,s1:/*,mb:*,ex:*/
+setlocal commentstring=//\ %s
 
 let b:undo_ftplugin = "setlocal comments< commentstring<"