tests: switch test from '--config ui.editor=~/foo' to HGEDITOR=~/foo...
tests: switch test from '--config ui.editor=~/foo' to HGEDITOR=~/foo
The test is currently not testing anything, the '--config ui.editor=~/path'
argument is apparently of lower priority than the HGEDITOR that run-tests.py is
setting.
Differential Revision:
https://phab.mercurial-scm.org/D1809