gnucash stable: Update another old version reference

[Geert Janssens]

Updated	 via  https://github.com/Gnucash/gnucash/commit/4de4132c (commit)
	from  https://github.com/Gnucash/gnucash/commit/16c93c80 (commit)



commit 4de4132c4299281e74604793c75a5fff6e2bef3c
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Sun Apr 16 09:30:37 2023 +0200

    Update another old version reference

diff --git a/README b/README
index 1a535cdb2c..deb12c2559 100644
--- a/README
+++ b/README
@@ -156,7 +156,7 @@ details.
 Supported Platforms
 -------------------
 
-GnuCash 3.x is known to work with the following operating systems:
+GnuCash 5.x is known to work with the following operating systems:
 
 GNU/Linux             -- x86, Sparc, PPC
 FreeBSD               -- x86



Summary of changes:
 README | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)