Bump psutil from 5.6.3 to 5.6.6 in /examples/distillation

Bumps [psutil](https://github.com/giampaolo/psutil) from 5.6.3 to 5.6.6.
- [Release notes](https://github.com/giampaolo/psutil/releases)
- [Changelog](https://github.com/giampaolo/psutil/blob/master/HISTORY.rst)
- [Commits](https://github.com/giampaolo/psutil/compare/release-5.6.3...release-5.6.6

)
Signed-off-by: dependabot[bot] <support@github.com>

examples/distillation/requirements.txt

@@ -3,5 +3,5 @@ transformers
 gitpython==3.0.2
 tensorboard>=1.14.0
 tensorboardX==1.8
-psutil==5.6.3
+psutil==5.6.6
 scipy==1.3.1