Maven 3.8.8 showing warnings for proguard-maven-plugin:2.6.0

[william-ferguson-au]

Maven 3.8.8 showing warnings for proguard-maven-plugin:2.6.0

[WARNING] 
[WARNING] Plugin validation issues were detected in 1 plugin(s)
[WARNING] 
[WARNING]  * com.github.wvengen:proguard-maven-plugin:2.6.0
[WARNING]   Declared at location(s):
[WARNING]    * au.com.foo:bar23.1.0-SNAPSHOT (pom.xml) @ line 495
[WARNING]   Used in module(s):
[WARNING]    * au.com.foo:bar:23.1.0-SNAPSHOT (pom.xml)
[WARNING]   Plugin issue(s):
[WARNING]    * Plugin is a Maven 2.x plugin, which will be not supported in Maven 4.x
[WARNING]    * Plugin mixes multiple Maven versions: [3.8.6, 2.0]
[WARNING]    * Plugin should declare these Maven artifacts in `provided` scope: [org.apache.maven:maven-plugin-api:3.8.6]
[WARNING]    * Plugin depends on plexus-container-default, which is EOL
[WARNING] 
[WARNING] 
[WARNING] Fix reported issues by adjusting plugin configuration or by upgrading above listed plugins. If no upgrade available, please notify plugin maintainers about reported issues.
[WARNING] For more or less details, use 'maven.plugin.validation' property with one of the values (case insensitive): [BRIEF, DEFAULT, VERBOSE]
[WARNING] 

[lasselindqvist]

Relevant code: https://github.com/wvengen/proguard-maven-plugin/blob/master/pom.xml#L125

plexus-container-default is a transitive dependency via https://mvnrepository.com/artifact/org.apache.maven/maven-archiver/2.4

See #228 about the upgrade