fix: allow overriding of application service account

[razvan]

Description

Fixes #616

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• Changes are OpenShift compatible
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• Feature Tracker has been updated
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[sbernauer]

Nice fix, thanks and thanks for the test!
It would be nice if you could also assert the used ServiceAccount on the created Pods

[razvan]

Nice fix, thanks and thanks for the test! It would be nice if you could also assert the used ServiceAccount on the created Pods

done

[sbernauer]

Thanks! Sorry, I didn't know the assertion would be this complicated...

[razvan]

I had another typo but now ...

--- PASS: kuttl (101.23s)
    --- PASS: kuttl/harness (0.00s)
        --- PASS: kuttl/harness/overrides_openshift-false_spark-3.5.6 (99.72s)
PASS

[lfrancke]

Please add a release note snippet in the form "Previously, this went wrong. With this release, this was fixed in the following way."

[razvan]

Release Note

The service account of spark applications can now be overridden with pod overrides.

Previously the application service account was passed as command line argument to spark-submit
and was thus not possible to overwrite with pod overrides for the driver and executors.
This CLI argument has now been moved to the pod templates of the individual roles.