BUG: Fix backend domain parameter creation

[aloftus23]

🗣 Description

The Integration and Staging-cd (develop) have a conflicting parameter being created in the Terraform.

The terraform is setting the staging/domain variable to api.integration when it should remain api.staging-cd

Recreate:
Deploy Integration then deploy staging-cd. Integration will succeed but then staging-cd will get this error in the backend deploy:
Error:
Error: V1 - Make sure the 'api.integration.crossfeed.cyber.dhs.gov' exists.
Unable to create base path mapping for 'api.integration.crossfeed.cyber.dhs.gov':
Base path already exists for this domain name
at APIGatewayV1Wrapper. (/home/runner/work/XFD/XFD/backend/node_modules/serverless-domain-manager/dist/src/aws/api-gateway-v1-wrapper.js:104:23)
at Generator.throw ()
at rejected (/home/runner/work/XFD/XFD/backend/node_modules/serverless-domain-manager/dist/src/aws/api-gateway-v1-wrapper.js:6:65)
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

💭 Motivation and context

Staging-cd backend deployment fails after running the integration deployment.

🧪 Testing

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All future TODOs are captured in issues, which are referenced
  in code comments.
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated
  to reflect the changes in this PR.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.

✅ Pre-merge checklist

• Revert dependencies to default branches.
• Finalize version.

✅ Post-merge checklist

• Create a release.

[DJensen94]

Looks good