chore: disable v1 branch upkeep (#26218)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

.github/dependabot.yml

@@ -18,24 +18,6 @@ updates:
     labels:
       - "auto-approve"
     open-pull-requests-limit: 5
-
-  # run same dependabot upgrades on v1-main
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    target-branch: "v1-main"
-    schedule:
-      interval: "weekly"
-    labels: 
-      - "auto-approve"
-    open-pull-requests-limit: 5
-  - package-ecosystem: "pip"
-    directory: "/packages/@aws-cdk/lambda-layer-awscli"
-    target-branch: "v1-main"
-    schedule:
-      interval: "weekly"
-    labels: 
-      - "auto-approve"
-    open-pull-requests-limit: 5
 
   # Non-TypeScript init template dependency updates
   - package-ecosystem: "pip"

.github/workflows/yarn-upgrade-v1main.yml

@@ -1,9 +1,6 @@
 name: Yarn Upgrade v1-main
 
 on:
-  schedule:
-    # Every wednesday at 13:37 UTC
-    - cron: 37 13 * * 3
   workflow_dispatch: {}
 
 jobs: