gnucash maint: Fix the implementations of gnc_foo_get_day_neutral.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/3a35514d (commit)
	from  https://github.com/Gnucash/gnucash/commit/c6c5777c (commit)



commit 3a35514d84c30fb8a2263e00672dc651be7a7dc5
Author: John Ralls <jralls at ceridwen.us>
Date:   Fri Mar 19 17:09:03 2021 -0700

    Fix the implementations of gnc_foo_get_day_neutral.
    
    As implemented these returned 10:59 AM local on the day but neutral
    time is 10:59 UTC.



Summary of changes:
 libgnucash/engine/gnc-date.cpp | 16 +++++++++++-----
 libgnucash/engine/gnc-date.h   | 17 ++++-------------
 2 files changed, 15 insertions(+), 18 deletions(-)