Pin org.codehaus.plexus:plexus-utils to use v3.x.x to avoid pulling a…

…lpha dependencies

plexus-utils Maven from runtime can be overridden https://issues.apache.org/jira/browse/MNG-6965.
However, using 4.0.0 means, we need to add org.codehaus.plexus:plexus-xml:jar:4.0.3
because org.codehaus.plexus.util.xml.Xpp3Dom has been extracted in a sub-module.
And that pulls alpha dependencies (org.apache.maven:maven-api-xml). While it may work,
we should integrate alpha dependencies in a stable release.

.github/dependabot.yml

@@ -17,6 +17,9 @@ updates:
     target-branch: "main"
     ignore:
       - dependency-name: org.jruby:jruby
+      - dependency-name: org.codehaus.plexus:plexus-utils
+        update-types:
+          - "version-update:semver-major"
       - dependency-name: org.glassfish.jaxb:jaxb-runtime
         update-types:
           - "version-update:semver-major"