Add deployment tier to CI_JOB_JWT

What does this MR do and why?

Related to #363590 (closed)

Screenshots or screen recordings

Used https://jwt.io/ to decode the payloads.

deployment_tier is not in $CI_JOB_JWT from a non-deployment job:

{
  "namespace_id": "1",
  "namespace_path": "root",
  "project_id": "21",
  "project_path": "root/go-app",
  "user_id": "1",
  "user_login": "root",
  "user_email": "admin@example.com",
  "pipeline_id": "44",
  "pipeline_source": "web",
  "job_id": "615",
  "ref": "main",
  "ref_type": "branch",
  "ref_protected": "true",
  "jti": "de25c618-cb9b-49cc-a439-191167be5f9d",
  "iss": "127.0.0.1",
  "iat": 1656605611,
  "nbf": 1656605606,
  "exp": 1656609211,
  "sub": "job_615"
}

deployment_tier is in $CI_JOB_JWT from a deployment job (environment: production):

{
  "namespace_id": "1",
  "namespace_path": "root",
  "project_id": "21",
  "project_path": "root/go-app",
  "user_id": "1",
  "user_login": "root",
  "user_email": "admin@example.com",
  "pipeline_id": "44",
  "pipeline_source": "web",
  "job_id": "616",
  "ref": "main",
  "ref_type": "branch",
  "ref_protected": "true",
  "environment": "production",
  "environment_protected": "false",
  "deployment_tier": "production",
  "jti": "4dd7468a-07ef-4e6d-8c4b-366706d782b7",
  "iss": "127.0.0.1",
  "iat": 1656605614,
  "nbf": 1656605609,
  "exp": 1656609214,
  "sub": "job_616"
}

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