Add checkstyle to CI
diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index 001e7b5..e07577b 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -21,14 +21,16 @@
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up JDK 11
-      uses: actions/setup-java@v3
+    - run: |
+        wget -O $RUNNER_TEMP/java_package.tar.gz -c --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u131-b11/d54c1d3a095b4ff2b6607d096fa80163/jdk-8u131-linux-x64.tar.gz
+    - uses: actions/setup-java@v3
       with:
-        java-version: '11'
-        distribution: 'temurin'
-        cache: maven
+        distribution: 'jdkfile'
+        jdkFile: ${{ runner.temp }}/java_package.tar.gz
+        java-version: '8.0.0'
+        architecture: x64
     - name: Build with Maven
-      run: mvn -B package --file pom.xml
+      run: mvn -B package checkstyle:check findbugs:check --file pom.xml
 
     # Optional: Uploads the full dependency graph to GitHub to improve the quality of Dependabot alerts this repository can receive
     - name: Update dependency graph