v1.0.10: rename getCommand() to getCommands()

The method DServices4J#getCommand() was renamed to DServices4J#getCommands() to match the name of the Commands class.

<repositories>
  <repository>
    <id>Bintray</id>
    <url>https://jcenter.bintray.com</url>
  </repository>
</repositories>

<dependencies>
  <dependency>
    <groupId>net.discordservices</groupId>
    <artifactId>DServices4J</artifactId>
    <version>1.0.10</version>
  </dependency>
</dependencies>

repositories{
  jcenter()
}

dependencies{
  implementation 'net.discordservices:DServices4J:1.0.10'
}