[PLT-1246] [GKE] Soportar CMEK para los discos root de los workers

[iamjanr]

Description

Soportar CMEK y SA para los nodepools

Related Pull Requests

N/A

Pull Request Checklist:

• [PR title] Include a title referencing a ticket in Jira (e.g. "[CLOUDS-99] Implement a new funcionality").
• [PR desc] Add a summary of the changes made in simple terms.
• [PR desc] List any pull-request related to this change (docs, tests, feature, etc.).
• [PR labels] Add the corresponding labels (release, skips, cherry-pick, AT-eks-smoke, etc).
• [Docs] Are changes to the documentation required? (if so, please add references to those PRs).
• [QA] Are new unit tests required according with the changes? (if so, please add references to those PRs).

JIRA: https://stratio.atlassian.net/browse/PLT-1246