gnucash-docs maint: Guide:C: Fix image declarations

[Frank H.Ellenberger]

Updated	 via  https://github.com/Gnucash/gnucash-docs/commit/540f0cef (commit)
	from  https://github.com/Gnucash/gnucash-docs/commit/51374741 (commit)



commit 540f0cef70b96bb025f4096e73828e158e05d209
Author: Frank H. Ellenberger <frank.h.ellenberger at gmail.com>
Date:   Sun Oct 9 22:40:54 2022 +0200

    Guide:C: Fix image declarations
    
    Some were not proper scaled.
    Now all appear in the List of Figures.



Summary of changes:
 guide/C/ch_accts.xml        |  205 ++--
 guide/C/ch_basics.xml       |  179 ++-
 guide/C/ch_bus_features.xml |  315 ++----
 guide/C/ch_capgain.xml      |   97 +-
 guide/C/ch_cbook.xml        |  391 ++++---
 guide/C/ch_cc.xml           |  417 ++++---
 guide/C/ch_currency.xml     |  904 +++++++---------
 guide/C/ch_dep.xml          |   80 +-
 guide/C/ch_invest.xml       | 2511 +++++++++++++++++++------------------------
 guide/C/ch_loans.xml        |  255 ++---
 guide/C/ch_oview.xml        |   37 +-
 guide/C/ch_txns.xml         |  894 +++++++--------
 12 files changed, 2744 insertions(+), 3541 deletions(-)