Add spotless integration for mvn and GitHub

Author: franz1981

.github/workflows/loom-tests.yml

@@ -45,4 +45,4 @@ jobs:
         restore-keys: ${{ runner.os }}-m2
 
     - name: Build with Maven
-      run: mvn -B package --file pom.xml
+      run: mvn -B verify --file pom.xml -DargLine="--enable-preview"

pom.xml

@@ -49,6 +49,32 @@
     </dependencyManagement>
 
     <build>
+        <plugins>
+            <plugin>
+                <groupId>com.diffplug.spotless</groupId>
+                <artifactId>spotless-maven-plugin</artifactId>
+                <version>3.0.0</version>
+                <configuration>
+                    <java>
+                        <eclipse />
+                    </java>
+                </configuration>
+                <executions>
+                    <execution>
+                        <phase>compile</phase>
+                        <goals>
+                            <goal>apply</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                        <phase>verify</phase>
+                        <goals>
+                            <goal>check</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
         <pluginManagement>
             <plugins>
                 <plugin>