chore: exempt the spec update PRs from usual PR requirements (#26548)

This is needed so these PRs will merge without manual intervention.

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

Author: mrgrain

.github/workflows/spec-update.yml

@@ -81,7 +81,7 @@ jobs:
           title: 'feat: update AWS Service Spec'
           body: |-
              AWS Service Spec packages to latest versions.
-          labels: contribution/core,dependencies,auto-approve
+          labels: contribution/core,dependencies,auto-approve,pr-linter/exempt-integ-test,pr-linter/exempt-readme,pr-linter/exempt-test
           team-reviewers: aws-cdk-team
           # Github prevents further Github actions to be run if the default Github token is used.
           # Instead use a privileged token here, so further GH actions can be triggered on this PR.