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
http://example.com/no/anchor, branches: (None, [])
http://example.com/an/anchor, branches: ('foo', [])
http://example.com/no/anchor/branches, branches: (None, ['foo'])
http://example.com/an/anchor/branches, branches: ('bar', ['foo'])
http://example.com/an/anchor/branches-None, branches: ('foo', [])