gnucash maint: [register] simplify gnc:register-report-create-internal

[Christopher Lam]

Updated	 via  https://github.com/Gnucash/gnucash/commit/286dc50d (commit)
	from  https://github.com/Gnucash/gnucash/commit/d2e01320 (commit)



commit 286dc50ddc74c435ed351ef60b1d64590a5c3531
Author: Christopher Lam <christopher.lck at gmail.com>
Date:   Sat Jan 1 09:06:39 2022 +0800

    [register] simplify gnc:register-report-create-internal
    
    and deprecate the currently unused invoice? option.



Summary of changes:
 gnucash/report/reports/standard/register.scm | 41 ++++++++++++----------------
 1 file changed, 18 insertions(+), 23 deletions(-)