Allow the extra field to be used

[tomellis91]

Description

Please include a summary of the change and which issue is fixed.
List any dependencies that are required for this change.

Fixes # (issue)
This PR allows the use of the extra field that was already present in the executor struct. This will allow for additional run time options to be set in the kubectl run command.

The changes in this PR include:

• read the config value for extra and set in the existing executor
• reference the extra field in the executor during instantiation
• Update README.md with and example of passing in a nodeSelector patch

This is a non breaking change and takes advantage of the original struct fields.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Documentation

• the change is mentioned in the ## [Unreleased] section of CHANGELOG.md
• the configuration yaml was changed and the example config in README.md was updated
• a usage example was added to README.md
• tests for the changes have been implemented (see: Testing your changes)

[d-rk]

@tomellis91 thank you for the contribution. I merged it and it is already included in the latest release: https://github.com/deviceinsight/kafkactl/releases/tag/v3.2.0

[tomellis91]

hey @d-rk ,
It looks like the functionality for the Extra config doesn't exist anymore/ has been replaced.

Was there a specific reason for the removal of the functionality?

[d-rk]

Hey @tomellis91

I have added specific overrides for Labels, Annotations, NodeSelector with 1ef06d6.

The new configurations are simpler as you no longer need to specify the entire override.

The extra configuration was more flexible, but I decided to drop it as the three new configurations should cover most cases. If I kept them, I would have to deserialize/merge them into the override structure, and since I also only have limited resources for this, I decided to drop them.