fix(rez-build): pass both the parser and the group to bind cli

Passing only the group is causing a regression where the custom
arguments defined in parse_build_args.py are not properly set
as attributes.

Relates [#587](#587)

src/rez/cli/build.py

@@ -46,7 +46,7 @@ def setup_parser_common(parser):
             cls_ = clss[0]
             title = "%s build system arguments" % cls_.name()
             group = parser.add_argument_group(title)
-            cls_.bind_cli(group)
+            cls_.bind_cli(parser, group)
 
         types = [x.name() for x in clss]
     else: