[misc] Apply xar:format
XWIKI-9939: Spurious warning "Annotation could not be loaded" on the history page, if annotations are enabled
* Apply new XAR format.
XWIKI-9939: Spurious warning "Annotation could not be loaded" on the history page, if annotations are enabled
* Don't load the annotations if the document content ('xwikicontent') is not present.