🌱 Enable dependabot multi-directory updates

[spencerschrock]

What kind of change does this PR introduce?

ci update

• PR title follows the guidelines defined in our pull request documentation

What is the current behavior?

• We get multiple PRs for the same update, across multiple PRs
  • Go example:
    • 🌱 Bump github.com/onsi/ginkgo/v2 from 2.17.1 to 2.17.2 #4056
    • 🌱 Bump github.com/onsi/ginkgo/v2 from 2.17.1 to 2.17.2 in /tools #4058
  • Docker example:
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /cron/internal/worker #4007
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /cron/internal/webhook #4008
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /attestor #4009
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /cron/internal/cii #4010
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /cron/internal/bq #4011
    • 🌱 Bump golang from 1.22.1 to 1.22.2 #4012
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /clients/githubrepo/roundtripper/tokens/server #4013
    • 🌱 Bump golang from 1.22.1 to 1.22.2 in /cron/internal/controller #4014

What is the new behavior (if this is a feature change)?**

We use dependabot's new beta feature:
https://github.blog/changelog/2024-04-29-dependabot-multi-directory-configuration-public-beta-now-available/

this does not group all Go updates, or all Docker updates. But for any single updates to these dependencies that exist in multiple lockfiles, they will all be updated in 1 PR.

• Tests for the changes have been added (for bug fixes/features)

Which issue(s) this PR fixes

NONE

Special notes for your reviewer

Does this PR introduce a user-facing change?

For user-facing changes, please add a concise, human-readable release note to
the release-note

(In particular, describe what changes users might need to make in their
application as a result of this pull request.)

NONE