…inor version

When an error occurs, this information is provided by handleArtifacts.

For warnings, the only information is the information provided by the getLog().warn() call itself.

Without this change, the following output is common:
[INFO] --- maven-enforcer-plugin:3.0.0-M2:enforce (display-info) @ acceptance-test-harness ---
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53
[WARNING] Invalid bytecodeVersion for module-info.class: expected 52, but was 53

…eVersion.java

Co-authored-by: Mirko Friedenhagen <[email protected]>