setup Java in release workflow

This is needed in order for the SETH tests to run without erroring.
These weren't running before anyway because the model pack wasn't set,
which meant that those tests were skipped anyway, so we never realised
that this was a potential issue.

.github/workflows/release.yml

@@ -33,6 +33,12 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
+      - name: Set up JDK 11
+        uses: actions/setup-java@v3
+        with:
+          java-version: '11'
+          distribution: 'temurin'
+
       - name: bump version without commit or tag and build
         id: build
         run: |