v0.1.5: Update jenkins base image to 2.204.2-slim

2.204.2 is the current LTS release from the time being

v0.1.4: Update plugins.txt & update dockerfile for kubernetes plugin

Update plugins to pickup fix for origin headers found here https://github.com/fabric8io/kubernetes-client/pull/1669

v0.1.3: Remove credentials plugin to avoid dependency confilct

Problem:
credentials-binding has dependency of "SSH Credentials" plugin. On installation it implicitly installs the latest "SSH Credentials" plugin as the dependency, which requires a newer v2.2.0 credentials plugin, so the claimed plugin version is not satisfied.

Solution:
Remove credentials plugin from the list, a proper version of it will be installed by dependencies.

v0.1.1

Use install-plugins script to cache required plugins in the image