deps: update actions/setup-java action to v4 (#1629)

* 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

---------

Co-authored-by: Lawrence Qiu <[email protected]>
Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: 3 people

.github/workflows/unmanaged_dependency_check.yaml

@@ -5,8 +5,8 @@ jobs:
   unmanaged_dependency_check:
     runs-on: ubuntu-latest
     steps:
+      - uses: actions/setup-java@v4
       - uses: actions/checkout@v4
-      - uses: actions/setup-java@v3
         with:
           distribution: temurin
           java-version: 11