Feature/707

[filippomc]

Closes #707

Implemented solution: the volume has been removed from the deployment

How to test this PR: set backups: true in the values-template.yaml and verify that the db-backups volume is not mounted to the database pod.

Sanity checks:

• [x] The pull request is explicitly linked to the relevant issue(s)
• [x] The issue is well described: clearly states the problem and the general proposed solution(s)
• [x] From the issue and the current PR it is explicitly stated how to test the current change
• [x] The labels in the issue set the scope and the type of issue (bug, feature, etc.)
• [x] All the automated test checks are passing
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Breaking changes (select one):

• [x] The present changes do not change the preexisting api in any way
• [ ] This PR and the issue are tagged as a breaking-change

Possible deployment updates issues (select one):

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• [ ] This PR and the issue are tagged as alert:deployment

Test coverage (select one):

• [ ] Tests for the relevant cases are included in this pr
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