gnucash-docs maint: Fix html build failure

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash-docs/commit/b196fb0b (commit)
	from  https://github.com/Gnucash/gnucash-docs/commit/dba3a713 (commit)



commit b196fb0b88efc39abb53fafb518c883c6ce288d0
Author: John Ralls <jralls at ceridwen.us>
Date:   Sat Jul 9 16:22:02 2022 -0700

    Fix html build failure
    
    styletrigger and figtrigger must depend on htmltrigger.



Summary of changes:
 cmake/AddHtmlTarget.cmake | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)