Add the javadoc plugin for virtual thread executor plugin (#752)

Author: peachisai

test/plugin/scenarios/jdk-virtual-thread-executor-scenario/pom.xml

@@ -98,6 +98,39 @@
                     <target>21</target>
                 </configuration>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <id>attach-javadocs</id>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <failOnError>false</failOnError>
+                </configuration>
+            </plugin>
+            <!-- Ignore the error of javadoc build -->
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <id>empty-javadoc-jar</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                        <configuration>
+                            <classifier>javadoc</classifier>
+                            <classesDirectory>${basedir}/javadoc</classesDirectory>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
         </plugins>
     </build>
 </project>