settings.xml

<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">

  <profiles>
    <profile>
      <id>allow-snapshots</id>
      <activation><activeByDefault>true</activeByDefault></activation>
      <pluginRepositories>
        <pluginRepository>
          <id>sonatype-snapshots</id>
          <url>https://oss.sonatype.org/content/repositories/snapshots</url>
          <releases><enabled>false</enabled></releases>
          <snapshots><enabled>true</enabled></snapshots>
        </pluginRepository>
      </pluginRepositories>
      <repositories>
        <repository>
          <id>sonatype-snapshots</id>
          <url>https://oss.sonatype.org/content/repositories/snapshots</url>
          <releases><enabled>false</enabled></releases>
          <snapshots><enabled>true</enabled></snapshots>
        </repository>
      </repositories>
    </profile>
  </profiles>
</settings>