gnucash-docs maint: fix minor typo

[Frank H.Ellenberger]

Updated	 via  https://github.com/Gnucash/gnucash-docs/commit/cb180053 (commit)
	from  https://github.com/Gnucash/gnucash-docs/commit/345096a2 (commit)



commit cb1800539d02138851de66e0520f25c3ae583f94
Author: Daniel Brown <djbrown at users.noreply.github.com>
Date:   Sat Apr 17 20:07:57 2021 +0200

    fix minor typo



Summary of changes:
 guide/de/ch_txns.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)