gnucash maint: Fix a typo in gir error message

[Frank H.Ellenberger]

Updated	 via  https://github.com/Gnucash/gnucash/commit/a28f27a0 (commit)
	from  https://github.com/Gnucash/gnucash/commit/de06e900 (commit)



commit a28f27a0e1f127f6f4904304e2e4f68e48fd6749
Author: fell <frank.h.ellenberger at gmail.com>
Date:   Tue Oct 3 19:42:32 2017 +0200

    Fix a typo in gir error message



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