migrate api_shield_operation to framework

[BrendanBall]

This PR migrates cloudflare_api_shield_operation to the terraform-plugin-framework to fix a bug caused by the API returning a normalized version of a specified attribute that causes mismatches between resource config and state, resulting in the resource having to be recreated on every terraform apply. This is due to not following the expectations of terraform mentioned in https://github.com/hashicorp/terraform/blob/main/docs/resource-instance-change-lifecycle.md:

Normalization: the remote API has returned some data in a different form than was recorded in the Previous Run State, but the meaning is unchanged.
In this case, the provider should return the exact value from the Previous Run State, thereby preserving the value as it was written by the user in the configuration and thus avoiding unwanted cascading changes to elsewhere in the configuration.

Migrating to the framework is necessary to implement semantic equality between the unnormalized config and the normalized state returned from the API which is used during terraform plan/apply.

[github-actions]

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[maciej]

lgtm, left one comment, though.

(I can't approve because of lack access)