Upgrade GitHub Actions versions

Update workflow actions across CI, release, snapshot and labeler workflows: actions/checkout@v4 -> actions/checkout@v6, actions/setup-java@v4 -> actions/setup-java@v5, and actions/labeler@v5 -> actions/labeler@v6. Keeps workflows current and ensures compatibility with the configured Java 25 setup.

Author: jcputney

.github/workflows/ci.yml

@@ -14,10 +14,10 @@ jobs:
         java-version: [25]
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up JDK ${{ matrix.java-version }}
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@v5
         with:
           java-version: ${{ matrix.java-version }}
           distribution: temurin

.github/workflows/labeler.yml

@@ -12,6 +12,6 @@ jobs:
   label:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/labeler@v5
+      - uses: actions/labeler@v6
         with:
           sync-labels: true

.github/workflows/release.yml

@@ -16,11 +16,11 @@ jobs:
       contents: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: webfactory/ssh-agent@v0.9.1
         with:
           ssh-private-key: ${{ secrets.MAVEN_RELEASE_SSH_KEY }}
-      - uses: actions/setup-java@v4
+      - uses: actions/setup-java@v5
         with:
           java-version: "25"
           distribution: "temurin"

.github/workflows/snapshot.yml

@@ -24,9 +24,9 @@ jobs:
       checks: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
-      - uses: actions/setup-java@v4
+      - uses: actions/setup-java@v5
         with:
           java-version: "25"
           distribution: "temurin"