Add jacoco for test coverage reporting

Author: testower

gbfs-validator-java-cli/pom.xml

@@ -22,6 +22,9 @@
         <picocli.version>4.7.7</picocli.version>
         <jackson.version>2.15.2</jackson.version>
         <junit.version>5.10.2</junit.version>
+        <jacoco-maven-plugin.version>0.8.13</jacoco-maven-plugin.version>
+        <!-- empty argLine property, the value is set up by Jacoco during unit tests execution -->
+        <argLine></argLine>
     </properties>
 
     <dependencies>
@@ -142,6 +145,37 @@
                 </executions>
             </plugin>
 
+            <!-- Jacoco for code coverage -->
+            <plugin>
+                <groupId>org.jacoco</groupId>
+                <artifactId>jacoco-maven-plugin</artifactId>
+                <version>${jacoco-maven-plugin.version}</version>
+                <executions>
+                    <execution>
+                        <id>default-prepare-agent</id>
+                        <goals>
+                            <goal>prepare-agent</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                        <id>default-report</id>
+                        <phase>prepare-package</phase>
+                        <goals>
+                            <goal>report</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                        <id>default-check</id>
+                        <goals>
+                            <goal>check</goal>
+                        </goals>
+                        <configuration>
+                            <rules />
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+
             <!-- Surefire for tests -->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>