Update Jenkins plugins: 2019Q3 → 2019Q4 edition

Originally created by @intrigeri on #16954 (Redmine)

Updating those that have CVEs is already covered by sysadmin shifts. This is about updating all plugins as we can’t rely on every security issue to get a CVE and there’s no LTS with security support.

This includes giving a crash course to groente + zen so they know how to do that.

Related issues

Blocked by #10068 (closed)

Edited May 15, 2020 by intrigeri

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information