Add Mirroring resources to Network Security.

[modular-magician]

This PR is a promotion from google-private provider.
Removal CL: https://cloud-internal-review.git.corp.google.com/c/cloud-graphite-eng/magic-modules-private-overrides/+/49230

All Mirroring resources are bundled together in one PR because they're dependent on one another and cannot be tested separately.

`google_network_security_mirroring_deployment`, `google_network_security_mirroring_deployment_group`, `google_network_security_mirroring_endpoint_group_association`, `google_network_security_mirroring_endpoint_group`

Derived from GoogleCloudPlatform/magic-modules#12420

[github-actions]

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