gnucash maint: Use macos-latest github runner for mac tests.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/1d5e9d4d (commit)
	from  https://github.com/Gnucash/gnucash/commit/b98cd009 (commit)



commit 1d5e9d4d97dec5c16733d09b67e96fb11ed566f3
Author: John Ralls <jralls at ceridwen.us>
Date:   Thu Jul 28 11:49:51 2022 -0700

    Use macos-latest github runner for mac tests.



Summary of changes:
 .github/workflows/mac-tests.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)