Bump node from 14.17.6-slim to 16.10.0-slim in /docker (from PR #2422)
Bump node from 14.17.6-slim to 16.10.0-slim in /docker (from PR #2422)

Bumps node from 14.17.6-slim to 16.10.0-slim.

mozilla-services/tecken,mozilla-services/tecken,mozilla-services/tecken,mozilla-services/tecken