DATA-2827 Removes lazy suffix from input mime type

[bhaney]

Sometimes RDK will append +lazy to the mime type string to specify it as a lazy encoded image.
Python SDK doesn't require this, as all images are default lazy encoded, and also +lazy will cause an error of

ValueError - 'image/jpeg+lazy' is not a valid CameraMimeType - file_name='enum.py' func_name='__new__' line_num=702

Just checking for the +lazy suffix and removing it is enough to solve this issue