chore(deps): remove dependabot version updates (#240)

Renovate is the version-update bot on this Interactive repo. GitHub Dependabot alerts stay.

.github/dependabot.yml

@@ -1,36 +0,0 @@
-version: 2
-updates:
-  - package-ecosystem: "pip"
-    directories:
-      - "/src/slack-bot"
-      - "/src/weekly-post"
-      - "/src/roster-sync"
-      - "/src/ring-scheduler"
-      - "/src/holiday-router"
-      - "/src/release-notifier"
-      - "/src/shared"
-      - "/tests"
-    schedule:
-      interval: "weekly"
-    assignees:
-      - "amoussa1229"
-    commit-message:
-      prefix: "chore(deps)"
-    groups:
-      minor-and-patch:
-        update-types:
-          - "minor"
-          - "patch"
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-    assignees:
-      - "amoussa1229"
-    commit-message:
-      prefix: "chore(deps)"
-    groups:
-      minor-and-patch:
-        update-types:
-          - "minor"
-          - "patch"