Single CloudWatch logging role for API Gateways

[cvangerpen]

API Gateway's CloudWatch logging role is account- and region-specific. This moves that role's creation to a single place rather than in both the cirrus and stac-server module as that leads to constant state drift.

Related issue(s)

• N/A

Proposed Changes

1. Remove the aws_api_gateway_account Terraform resource from the stac-server and cirrus module since having multiple instances will result in Terraform consistently switching between the two.
2. Create a single aws_api_gateway_account Terraform resource as part of the base_infra module such that all modules implementing API Gateways can rely on logging permissions being handled once elsewhere.

Testing

This change was validated by the following observations:

Without this change, every terraform apply would produce the following state difference (switching between stac-server and cirrus roles):

# module.filmdrop.module.cirrus[0].module.cirrus.module.builtin_functions.aws_api_gateway_account.cirrus_api_gateway_cw_role will be updated in-place
~ resource "aws_api_gateway_account" "cirrus_api_gateway_cw_role" {
    ~ api_key_version     = "4" -> (known after apply)
    ~ cloudwatch_role_arn = "arn:aws:iam::123456789012:role/fd-example-dev-stac-server-us-west-2" -> "arn:aws:iam::123456789012:role/fd-kodiak-dev-cirrus-us-west-2"
    ~ features            = [
        - "UsagePlans",
    ] -> (known after apply)
    id                  = "api-gateway-account"
    ~ throttle_settings   = [
        - {
            - burst_limit = 5000
            - rate_limit  = 10000
        },
    ] -> (known after apply)
}

Plan: 0 to add, 1 to change, 0 to destroy.

After applying this commit and redeploying, Terraform correctly reports that no resources have changed for consecutive apply's.

Checklist

• I have deployed and validated this change
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