Authenticate Dependabot jobs for higher rate limits

Authenticated requests are limited to 1,000 per hour, while unauthenticated requests are limited to 60 per hour. Issue: PGO-2555

Author: cbandy

.github/dependabot.yml

@@ -12,12 +12,25 @@
 # There is a hack to have *two* schedules: https://github.com/dependabot/dependabot-core/issues/1778#issuecomment-1988140219
 ---
 version: 2
+
+registries:
+ # Authenticate to GitHub for higher API rate limits
+ # https://docs.github.com/en/rest/using-the-rest-api/rate-limits-for-the-rest-api
+ # https://docs.github.com/en/actions/how-tos/security-for-github-actions/security-guides/automatic-token-authentication
+ # https://docs.github.com/en/code-security/dependabot/working-with-dependabot/configuring-access-to-private-registries-for-dependabot#git
+ github:
+ type: git
+ url: https://github.com
+ username: x-access-token
+ password: ${{ secrets.GITHUB_TOKEN }}
+
 updates:
  - package-ecosystem: github-actions
  directories:
  # "/" is a special case that includes ".github/workflows/*"
  - '/'
  - '.github/actions/*'
+ registries: '*'
  schedule:
  interval: weekly
  day: tuesday
@@ -36,6 +49,7 @@ updates:
 
  - package-ecosystem: gomod
  directory: '/'
+ registries: '*'
  schedule:
  interval: weekly
  day: wednesday