Cortex cleanup

[dms1981]

A reference to the issue / Description of it

#7607

How does this PR fix the problem?

Removes Cortex user now that the role is being used, updates documentation to reflect this.

How has this been tested?

Tested through CI pipeline

Deployment Plan / Instructions

Deploy through CI

Checklist (check x in [ ] of list items)

• I have performed a self-review of my own code
• All checks have passed
• I have made corresponding changes to the documentation
• Plan and discussed how it should be deployed to PROD (If needed)

Additional comments (if any)

{Please write here}

[github-actions]

Trivy Scan Failed

Show Output

```hcl

---

Trivy will check the following folders:
terraform/environments/core-logging

---

Running Trivy in terraform/environments/core-logging
2024-10-10T12:00:31Z INFO [vulndb] Need to update DB
2024-10-10T12:00:31Z INFO [vulndb] Downloading vulnerability DB...
2024-10-10T12:00:31Z INFO [vulndb] Downloading artifact... repo="ghcr.io/aquasecurity/trivy-db:2"
2024-10-10T12:00:31Z ERROR [vulndb] Failed to download artifact repo="ghcr.io/aquasecurity/trivy-db:2" err="OCI repository error: 1 error occurred:\n\t* GET https://ghcr.io/v2/aquasecurity/trivy-db/manifests/2: TOOMANYREQUESTS: retry-after: 540.077µs, allowed: 44000/minute\n\n"
2024-10-10T12:00:31Z FATAL Fatal error init error: DB error: failed to download vulnerability DB: OCI artifact error: failed to download vulnerability DB: failed to download artifact from any source
trivy_exitcode=1

</details> #### `Checkov Scan` Success
<details><summary>Show Output</summary>

```hcl

*****************************

Checkov will check the following folders:
terraform/environments/core-logging

*****************************

Running Checkov in terraform/environments/core-logging
Excluding the following checks: CKV_GIT_1,CKV_AWS_126,CKV2_AWS_38,CKV2_AWS_39
2024-10-10 12:00:34,136 [MainThread  ] [WARNI]  Failed to download module github.com/ministryofjustice/terraform-aws-observability-platform-tenant?ref=fbbe5c8282786bcc0a00c969fe598e14f12eea9b:None (for external modules, the --download-external-modules flag is required)
2024-10-10 12:00:34,136 [MainThread  ] [WARNI]  Failed to download module github.com/ministryofjustice/modernisation-platform-terraform-s3-bucket?ref=4e17731f72ef24b804207f55b182f49057e73ec9:None (for external modules, the --download-external-modules flag is required)
2024-10-10 12:00:34,136 [MainThread  ] [WARNI]  Failed to download module github.com/ministryofjustice/modernisation-platform-terraform-s3-bucket?ref=cadab519b10a7d28dfa3b77d407725db6b37614a:None (for external modules, the --download-external-modules flag is required)
2024-10-10 12:00:34,136 [MainThread  ] [WARNI]  Failed to download module github.com/ministryofjustice/modernisation-platform-terraform-s3-bucket?ref=8688bc15a08fbf5a4f4eef9b7433c5a417df8df1:None (for external modules, the --download-external-modules flag is required)
terraform scan results:

Passed checks: 400, Failed checks: 0, Skipped checks: 70


checkov_exitcode=0

CTFLint Scan Success

Show Output

*****************************

Setting default tflint config...
Running tflint --init...
Installing "terraform" plugin...
Installed "terraform" (source: github.com/terraform-linters/tflint-ruleset-terraform, version: 0.9.1)
tflint will check the following folders:
terraform/environments/core-logging

*****************************

Running tflint in terraform/environments/core-logging
Excluding the following checks: terraform_unused_declarations
tflint_exitcode=0

Trivy Scan Failed

Show Output

*****************************

Trivy will check the following folders:
terraform/environments/core-logging

*****************************

Running Trivy in terraform/environments/core-logging
2024-10-10T12:00:31Z	INFO	[vulndb] Need to update DB
2024-10-10T12:00:31Z	INFO	[vulndb] Downloading vulnerability DB...
2024-10-10T12:00:31Z	INFO	[vulndb] Downloading artifact...	repo="ghcr.io/aquasecurity/trivy-db:2"
2024-10-10T12:00:31Z	ERROR	[vulndb] Failed to download artifact	repo="ghcr.io/aquasecurity/trivy-db:2" err="OCI repository error: 1 error occurred:\n\t* GET https://ghcr.io/v2/aquasecurity/trivy-db/manifests/2: TOOMANYREQUESTS: retry-after: 540.077µs, allowed: 44000/minute\n\n"
2024-10-10T12:00:31Z	FATAL	Fatal error	init error: DB error: failed to download vulnerability DB: OCI artifact error: failed to download vulnerability DB: failed to download artifact from any source
trivy_exitcode=1