domain1/docroot/featuredItems and multiple app servers

[pdurbin]

At https://guides.dataverse.org/en/6.8/installation/advanced.html#multiple-app-servers we say this:

"When users upload a logo or footer for their Dataverse collection using the “theme” feature described in the Dataverse Collection Management section of the User Guide, these logos are stored only on the app server the user happened to be on when uploading the logo. By default these logos and footers are written to the directory /usr/local/payara6/glassfish/domains/domain1/docroot/logos."

However, now that we've added featured items in this PR...

• Dataverse Featured Items support #11124

... we should update the docs above to mention that items under domain1/docroot/featuredItems also need to be considered.

[poikilotherm]

Please note that this folder will be ${STORAGE_DIR:/dv}/docroot/featuredItems by default in containers, so you might need to mount a different volume type there (in case of multiple servers this should obviously be of a ReadWriteMany type). IIRC we encourage people to mount some filesystem under ${STORAGE_DIR:/dv} already, but this may be a ReadWriteOnce type.

For both containerized and classic installations: if you have .../docroot on a ReadWriteMany filesystem already (NFS/SMB/...), you don't need to care about the featuredItems folder separately unless you want to have a different storage location or limitations applied.

It might be worth noting in the storage locations at https://guides.dataverse.org/en/latest/container/app-image.html#locations (Looks like we missed to add docroot there, too)