deps: update actions/setup-java action to v4 (googleapis#1978)

* deps: update actions/setup-java action to v4

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

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Author: renovate-bot

.github/workflows/unmanaged_dependency_check.yaml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-java@v3
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11