Using TCK Tested JDK builds of OpenJDK

The AdoptOpenJDK has been discontinued since July 2021 (https://adoptopenjdk.net). Switching the distribution to Azul Zulu. When using Zulu you get all the latest updated (TCK Tested) builds for all versions of OpenJDK

.github/workflows/build.yml

@@ -22,7 +22,7 @@ jobs:
       uses: actions/setup-java@v2
       with:
         java-version: ${{ matrix.java_version }}
-        distribution: 'adopt'
+        distribution: 'zulu'
     - name: Maven cache
       uses: actions/cache@v2
       env: