Update defaults for extra values to support lists

[domgoodwin]

Currently if you specify extraEnvs, extraVolumes or extraVolumeMounts it breaks the deployment. Updated so field looks for lists and not strings.

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[jmlrt]

jenkins test this please

[jmlrt]

related to #530

[jmlrt]

jenkins test this please

[domgoodwin]

There was an issue with the initContainer check, so I merged in latest from master

[jmlrt]

jenkins test this please

[domgoodwin]

Looking at the filebeat PR, would you suggest adding the same pattern - where if string use the old method if not parse the yaml?

[jmlrt]

jenkins test this please

[jmlrt]

Thanks you for this PR 👍

• Default values should be updated in README.md for extraVolumes, extraVolumeMounts, extraContainers and extraInitContainers.
• It would also be great if you could update the tests for this 4 values in https://github.com/elastic/helm-charts/blob/master/elasticsearch/tests/elasticsearch_test.py#L287-L341, similarly to what has been done in Accept a string as extraInitContainers value for filebeat #530

[domgoodwin]

I've updated with the requested changes now

[jmlrt]

jenkins test this please

[jmlrt]

Some changes are required to make Black formatter happy in elastic+helm-charts+pull-request+lint-python/149. Hope this is the last change to do.

[domgoodwin]

I think I've fixed the linting errors, the jenkins console log was hard to read honestly

[jmlrt]

jenlins test this please

[jmlrt]

LGTM, thank you 👍

[jmlrt]

backported to 7.7 branch in bcaaaad