use java 11 for utility workflow steps

Author: jodersky

.github/workflows/actions.yml

@@ -65,7 +65,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
-          java-version: 8
+          java-version: 11
       - name: Publish to Maven Central
         run: |
           if [[ $(git tag --points-at HEAD) != '' ]]; then
@@ -93,7 +93,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
-          java-version: '8'
+          java-version: '11'
       - name: Upload Example Zips
         run: ./mill uploadToGithub
 
@@ -112,7 +112,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
-          java-version: 8
+          java-version: 11
       - name: Generate Website
         run: |
           cd docs