HUE-8737 [core] Fix supervisor.py py3 compatible issue
HUE-8737 [core] Fix supervisor.py py3 compatible issue

kawamon/hue,cloudera/hue,kawamon/hue,kawamon/hue,kawamon/hue,cloudera/hue,cloudera/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue,kawamon/hue,kawamon/hue,kawamon/hue,kawamon/hue,cloudera/hue,kawamon/hue,kawamon/hue,cloudera/hue,cloudera/hue,cloudera/hue,kawamon/hue,cloudera/hue,cloudera/hue,kawamon/hue,kawamon/hue