gnucash maint: [category-barchart] simplify code

[Christopher Lam]

Updated	 via  https://github.com/Gnucash/gnucash/commit/5f06fc99 (commit)
	from  https://github.com/Gnucash/gnucash/commit/b79dffc5 (commit)



commit 5f06fc99fd1a4b7d30736a32656388cb8cb6f2b3
Author: Christopher Lam <christopher.lck at gmail.com>
Date:   Sat Feb 12 13:15:49 2022 +0800

    [category-barchart] simplify code



Summary of changes:
 .../report/reports/standard/category-barchart.scm  | 53 +++++++++++-----------
 1 file changed, 26 insertions(+), 27 deletions(-)