build(deps): bump psutil from 5.6.2 to 5.6.6 in /iceweasel

Bumps [psutil](https://github.com/giampaolo/psutil) from 5.6.2 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-5.6.2...release-5.6.6)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

iceweasel/requirements.txt

@@ -51,7 +51,7 @@ Markdown==3.1.1
 MarkupSafe==1.1.1
 medusa==0.5.4
 paramiko==2.4.2
-psutil==5.6.2
+psutil==5.6.6
 psycopg2==2.8.2
 pyasn1==0.4.5
 pyasn1-modules==0.2.5