test-subrepo-recursion: deleted default arguments
Deleted default arguments from test-sub-repo-recursion. Rationale is
that it is confusing to read, when the arguments aren't at each
command in the test
$ echo '[Section]' >> $HGRCPATH
$ echo 'KeY = Case Sensitive' >> $HGRCPATH
$ echo 'key = lower case' >> $HGRCPATH
$ hg showconfig Section
Section.KeY=Case Sensitive
Section.key=lower case