Feature Request: Reactor support for enforceBytecodeVersion in extra-enforcer-rules

[ches]

I have a situation where leaf application modules in a multi-module/Reactor build target Java 11, but a particular module needs to continue being able to run in Java 8 runtime environments, thus other library modules in the build that it depends on must also target 8.

I hoped that the enforceBytecodeVersion rule in extra-enforcer-rules would help to enforce this, but I tried the following configuration and the rule does not fail when class files of other modules that the one in question depends on are verifiably built with <release>11</release> / show major bytecode version 55 from javap.

<executions>
  <execution>
    <id>enforce-bytecode-version</id>
    <goals>
      <goal>enforce</goal>
    </goals>
    <configuration>
      <rules>
        <enforceBytecodeVersion>
          <maxJdkVersion>1.8</maxJdkVersion>
        </enforceBytecodeVersion>
      </rules>
      <fail>true</fail>
    </configuration>
  </execution>
</executions>

(also tried <maxJavaMajorVersionNumber>52</maxJavaMajorVersionNumber>)

So from cursory appearance, it seems the rule does not consider Reactor module dependencies. I didn't check implementation, I'm not acquainted with Maven plugin APIs, so apologies if I'm overlooking something.