ci: bump actions/setup-java from 5 to 6 in the actions group

Bumps the actions group with 1 update: [actions/setup-java](https://github.com/actions/setup-java).


Updates `actions/setup-java` from 5 to 6
- [Release notes](https://github.com/actions/setup-java/releases)
- [Commits](actions/setup-java@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-java
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
         with:
           submodules: true
       - name: Set up Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@v6
         with:
           distribution: temurin
           java-version: ${{matrix.java-version}}

.github/workflows/deploy.yml

@@ -20,7 +20,7 @@ jobs:
         with:
           submodules: true
       - name: Set up Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@v6
         with:
           distribution: temurin
           java-version: 25

.github/workflows/docs.yml

@@ -34,7 +34,7 @@ jobs:
         with:
           submodules: true
       - name: Set up Java
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@v6
         with:
           distribution: temurin
           java-version: 25