org.codehaus.mojo:properties-maven-plugin `set-system-properties` goal compatibility

http://www.mojohaus.org/properties-maven-plugin/usage.html has a goal called `set-system-properties` which can be used to set (you guessed it) system properties (as opposed to Maven properties) for specific Maven projects.

I use it to silence some particularly spammy Maven plugins which don't offer built-in verbosity options:
```xml

org.codehaus.mojo
properties-maven-plugin



set-system-properties




org.slf4j.simpleLogger.log.io.swagger.codegen.v3.AbstractGenerator
warn


org.slf4j.simpleLogger.log.io.swagger.codegen.v3.generators.DefaultCodegenConfig
error

```
This works perfectly well with `mvn`, but doesn't work with `mvnd`

If I run a build with the `-Dorg.slf4j.simpleLogger.showLogName` parameter, I can see that it's still the same log-producers.

So either the system properties aren't applied, or the way `mvnd` collects the logs results in strange behavior.

http://www.mojohaus.org/properties-maven-plugin/set-system-properties-mojo.html explicitly mentions:
> The goal is thread-safe and supports parallel builds.

So I'm guessing this is a `mvnd` issue.

Start by reproducing the properties-maven-plugin set-system-properties configuration with mvnd and compare it with mvn. Use the org.slf4j.simpleLogger.showLogName parameter and the log producers named in the report to determine whether system properties are not applied or whether mvnd's log collection causes the behavior. Done means the cause is identified and the compatibility issue is verified with a focused regression check.

Written by the indexing model from the issue text.