Findbugs plugin fails - Update maven-parent to Version 30 and downgrade maven-site-plugin

The solution is to Update :maven-parent:26 to Version 30.
Consequently after the update Fluido 1.3.0 fails [1] and the solution is to downgrage maven-site-plugin:3.5.1 to 3.4.

[1]:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-site-plugin:3.6:site (default-site) on project surefire: Velocity parsing error while reading the site decoration template from org.apache.maven.skins:maven-fluido-skin:jar:1.4 skin: Encountered "source" at META-INF/maven/site.vm[line 1162, column 52]
[ERROR] Was expecting one of:
[ERROR] "," ...
[ERROR] ")" ...
[ERROR] <WHITESPACE> ...