Site build fails because scannotation could not fetched

Since we introduced the javadoc of the platform in the site, builds on the apache server started to fail due a missing dependency:

[ERROR] Failed to execute goal on project marmotta-site: Could not resolve dependencies for project org.apache.marmotta:marmotta-site:pom:3.0.0-incubating-SNAPSHOT: Failed to read artifact descriptor for org.scannotation:scannotation:jar:1.0.3: Could not transfer artifact org.scannotation:scannotation:pom:1.0.3 from/to jboss (http://repository.jboss.org/nexus/content/groups/public/): Error transferring file: Operation not permitted -> [Help 1]

The source of the error comes from a wrong pom file in resteasy, which includes custom repositories. Sebastian already reported it: https://issues.jboss.org/browse/RESTEASY-855