Bump psutil from 5.6.3 to 5.6.6 (#34)

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](giampaolo/psutil@release-5.6.3...release-5.6.6)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements.txt

@@ -63,7 +63,7 @@ pip==19.1.1
 pluggy==0.12.0
 pockets==0.7.2
 posix-ipc==1.0.4
-psutil==5.6.3
+psutil==5.6.6
 psycopg2-binary==2.8.3
 py==1.8.0
 pyOpenSSL==19.0.0