Documentation Issue

[g1raffi]

Describe the bug
In the documentation of the installation via sidecar pattern, there is a Dockerfile example. The base image used in the image is a UBI8, but the package manager to install additional packages used is apt, which clearly will not work.

To Reproduce
Steps to reproduce the behavior:

1. Go to Custom Image and configuration via sidecar
2. Try to build the image

Expected behavior
Image for the sidecar should be buildable

Screenshots/Verbose output
None needed

Fix
Update the Dockerfile with either a different base image or update the package manager to yum

[wouter2397]

@werne2j Didn't know who to tag and I saw you commenting on some other issues...
This issue is still relevant.
Currently the docs do not deliver a working setup.

I'm willing to review and update the PR based on our internal working setup.
Are you then able to make sure the PR gets merged?