AdaptationSet should have the "profiles" attribute

[thenewguy]

RepresentationBase() maps "profile" to "@profiles" at

python-mpegdash/mpegdash/nodes.py

Line 395 in ca75790

self.profiles = parse_attr_value(xmlnode, 'profile', str)

and

python-mpegdash/mpegdash/nodes.py

Line 418 in ca75790

write_attr_value(xmlnode, 'profile', self.profiles)

Adaptation Sets can have the profiles attribute to signal conformance per

10.2.3.4. Adaptation Set Constraints
The @profiles parameter may be present to signal the constraints for the Adaptation Set

Probably a typo since there is @profile and also @profiles depending on the element