Use a single token for triage operations

What does this MR do and why?

Before merge

• Create a new @gitlab-bot token and set the GITLAB_BOT_API_TOKEN_ON_COM variable with it
• Check the current @gitlab-bot token on dev for expiration
• Create a new @gitlab-bot token on dev (if needed) and set the GITLAB_BOT_API_TOKEN_ON_DEV variable with it

After successful deploy

• Delete the GITLAB_COM_API_TOKEN, GITLAB_DEV_API_TOKEN, and GITLAB_BOT_AUTOMATED_TRIAGE_TOKEN variables
• Revoke the Scheduled triage operations at gitlab-org/quality/triage-ops and Reactive triage operations at gitlab-org/quality/triage-ops tokens (which expire on 2024-05-14 anyway)
• Delete the gitlab-com-api-token and gitlab-dev-api-token secrets from the cluster (I don't there are deleted automatically on deploy

Expected impact & dry-runs

No expected impact.

Action items

• If adding environment variables for reactive processors, update config/triage-web.yaml and .gitlab/ci/triage-web.yml
• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review

Closes #1504 (closed).