[3.1 backport] Introduced setting for disabling denormalized privilege data structures

[nibix]

Description

Backport from #5465

This introduces the setting plugins.security.privileges_evaluation.precomputed_privileges.enabled which can be used to disable the creation of denormalized privilege data structures. It is enabled by default to provide the best action throughput. It can make sense to disable the setting when it is seen that the initialisation process takes so much time/resources that it negatively affects the cluster performance (like observed in #5464) . This come at the price of a reduced action throughput.

• Category: Enhancement
• Why these changes are required? Operational safety
• What is the old behavior before changes and new behavior after changes? No behavioral changes.

Testing

• Unit testing

Check List

• New functionality includes testing
• New functionality has been documented
• Commits are signed per the DCO using --signoff

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[nibix]

This replaces #5483 as the CI there seems to be broken without any obvious way to fix

[nibix]

The CI seems to be weird here as well 🤔 possibly I need to do a dummy commit to get a different commit hash.