Sending email with attachment using Maven

Using surefire plugin and postman plugin, I am able to generate a surefire report and send email to a recipient. But the surefire report (html) is not getting attached with the email. Recipient is getting an email without the attachment. If I run the project again, email has been delivered with the attachment. Following is my pom.xml. I don't know what I am missing. Please help.

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.testing.example</groupId>
    <artifactId>SampleExample</artifactId>
    <packaging>jar</packaging>
    <name>SampleExample</name>
    <version>1.0.0</version>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>   
    </dependencies>
    <build>
        <sourceDirectory>src</sourceDirectory>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>ch.fortysix</groupId>
                <artifactId>maven-postman-plugin</artifactId>
                <version>0.1.6</version>
                <executions>
                    <execution>
                        <id>send_an_mail</id>
                        <phase>test</phase>
                        <goals>
                            <goal>send-mail</goal>
                        </goals>
                        <inherited>false</inherited>
                        <configuration>
                            <from>xxxxxxxxxx</from>
                            <subject>this is a test auto email sent from Eclipse using Maven</subject>
                            <htmlMessage>
                            <![CDATA[
                            <p>Hi, Please find attached.</p>
                            ]]>
                            </htmlMessage>
                            <failonerror>true</failonerror>
                            <mailhost>smtp.gmail.com</mailhost>
                            <mailport>465</mailport>
                            <mailssl>true</mailssl>
                            <mailAltConfig>true</mailAltConfig>
                            <mailuser>xxxxxxx</mailuser>
                            <mailpassword>xxxxxxx</mailpassword>
                            <receivers>
                                <receiver>xxxxxxxxx</receiver>
                            </receivers>

                            <fileSets>
                                <fileSet>
                                    <directory>${basedir}/target/site</directory>
                                    <includes>
                                        <include>**/surefire-report.html</include>
                                    </includes>
                                </fileSet>
                            </fileSets>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
    <reporting>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-report-plugin</artifactId>
                <version>2.18.1</version>
                <configuration>
                    <testFailureIgnore>true</testFailureIgnore>
                </configuration>
            </plugin>
        </plugins>
    </reporting>
</project>