chore: Add affinity to the ndm-operator deployment

[nearora-msft]

Pull Request template

Why is this PR required? What issue does it fix?:
This PR allows the user of the helm chart to set affinity to the ndm-operator pods.

What this PR does?:

Does this PR require any upgrade changes?:
No

If the changes in this PR are manually verified, list down the scenarios covered::

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Mention if this PR is part of any design or a continuation of previous PRs

Checklist:

• Fixes #
• PR Title follows the convention of <type>(<scope>): <subject>
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• Commit has integration tests
• (Optional) Are upgrade changes included in this PR? If not, mention the issue/PR to track:
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<type>(<scope>): <subject>.

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[niladrih]

@nearora-msft -- Thank you for this helm chart enhancement. We release a new chart for each new change, and as such need a version bump on the chart 'version'. Your PR needs a change in the https://github.com/openebs/node-disk-manager/blob/develop/deploy/helm/charts/Chart.yaml file, 'version' field. You'd have to bump the version to 2.1.1. The appVersion need not change, as there is no code change.

Also you'd have to sign your commit. We need our DCO!
I'll try to summarise the steps, but feel free to google this :P:

• Check if you name and email is set on your git config

     get config --get user.email

• If it's not set, set them using git config user.name "<your-name>", git config user.main "<your-email>
• Sign your commit:

git commit --amend -s --no-edit

[niladrih]

Needs a chart version bump