re-enable soundness checks (shell, python, and yaml)

Author: sebsto

.github/workflows/pull_request.yml

@@ -10,12 +10,12 @@ jobs:
     uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main
     with:
       license_header_check_project_name: "SwiftAWSLambdaRuntime"
-      shell_check_enabled: false
-      python_lint_check_enabled: false
+      shell_check_enabled: true
+      python_lint_check_enabled: true
       api_breakage_check_container_image: "swift:6.0-noble"
       docs_check_container_image: "swift:6.0-noble"
       format_check_container_image: "swiftlang/swift:nightly-6.0-jammy"
-      yamllint_check_enabled: false
+      yamllint_check_enabled: true
 
   unit-tests:
     name: Unit tests