gnucash-docs maint: Guide:C: Replace several wrong usages off "Help"

[Frank H.Ellenberger]

Updated	 via  https://github.com/Gnucash/gnucash-docs/commit/35217025 (commit)
	from  https://github.com/Gnucash/gnucash-docs/commit/88636417 (commit)



commit 35217025dd875f90138dfe637fe918093c676229
Author: Frank H. Ellenberger <frank.h.ellenberger at gmail.com>
Date:   Wed Feb 22 03:39:02 2023 +0100

    Guide:C: Replace several wrong usages off "Help"
    
    Protocol "help:"
    Link type "Help"—both are only under Linux available
    
    Document reference should be "Manual"



Summary of changes:
 guide/C/appendixd.xml       | 10 ++++------
 guide/C/ch_basics.xml       |  4 ++--
 guide/C/ch_bus_features.xml |  6 +++---
 guide/C/ch_cc.xml           |  2 +-
 guide/C/ch_expenses.xml     |  4 ++--
 guide/C/ch_importing.xml    |  2 +-
 guide/C/ch_invest.xml       |  4 ++--
 7 files changed, 15 insertions(+), 17 deletions(-)