Add VaultStaticSecret support to the keb

[ujvaritamas]

Description In order to stop using ArgoCD plugins, we need to replace our current mechanism for deploying secrets to the kcp clusters. The Vault Secrets Operator has been deployed to all 3 landscapes, and is now functional.

Everywhere where argo plugin was used -> the logic is changed to use the VSO.

Changes proposed in this pull request: Ticket: https://github.tools.sap/kyma/backlog/issues/5847

• Vault Secrets Operator used to get values from Vault (instead of the argo plugin)

• dev stage prod mount handled with corresponding global values:

• unused values (what use the argo vault plugin) deleted: https://github.tools.sap/kyma/management-plane-config/pull/5505

Related issue(s) https://github.tools.sap/kyma/backlog/issues/5847

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Add one of following labels

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[MarekMichali]

/kind enhancement