Fix 'mvn site' command

'mvn site' doesn't like the &amp;

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-site-plugin:3.2:site (default-site) on project fediz-idp: SiteToolException: Error parsing site descriptor: entity reference names can not start with character ' ' (position: START_DOCUMENT seen ...<project name="Apache Fediz IDP (Spring Security & ... @21:52) -> [Help 1