See Modifying Properties chapter of JMeter Maven Plugin wiki.
You need to add the following block to your <plugin>
section:
<configuration>
<propertiesUser>
<jmeter.reportgenerator.report_title>your-custom-title</jmeter.reportgenerator.report_title>
</propertiesUser>
</configuration>
Full pom.xml just in case:
<?xml version="1.0" encoding="UTF-8"?>
<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>org.example</groupId>
<artifactId>jmeter-maven</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<build>
<plugins>
<plugin>
<groupId>com.lazerycode.jmeter</groupId>
<artifactId>jmeter-maven-plugin</artifactId>
<version>3.4.0</version>
<executions>
<!-- Generate JMeter configuration -->
<execution>
<id>configuration</id>
<goals>
<goal>configure</goal>
</goals>
</execution>
<!-- Run JMeter tests -->
<execution>
<id>jmeter-tests</id>
<goals>
<goal>jmeter</goal>
</goals>
</execution>
<!-- Fail build on errors in test -->
<execution>
<id>jmeter-check-results</id>
<goals>
<goal>results</goal>
</goals>
</execution>
</executions>
<configuration>
<propertiesUser>
<jmeter.reportgenerator.report_title>your-custom-title</jmeter.reportgenerator.report_title>
</propertiesUser>
</configuration>
</plugin>
</plugins>
</build>
</project>
More information: How to Use the JMeter Maven Plugin