Dependency error in aem-maven-plugin when running maven 3.9+

[SWiggels]

Remove org.codehaus.plexus.util dependencies and replace with StringUtils and Stream-API.

Reason:
Maven 3.9.0 removed dependency backward compatibility to plexus-utils (see maven-3.9.0/release-notes)

Possible workaround for 2.0.16 is to define:

<groupId>com.unic.maven.plugins</groupId>
                    <artifactId>aem-maven-plugin</artifactId>
                    <version>2.0.16</version>
                    <dependencies>
                        <dependency>
                            <groupId>org.codehaus.plexus</groupId>
                            <artifactId>plexus-utils</artifactId>
                            <version>3.5.1</version>
                        </dependency>
                    </dependencies>
</plugin>

[CLAassistant]

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