collection_list.xml: use a <feed> of <entry>s
Instead of having a single that contains a tag that contains a list of
- Follows the spirit of Atom
- Follows the AtomPub spec https://datatracker.ietf.org/doc/html/rfc5023#section-5.2 and the SWORD spec http://swordapp.github.io/SWORDv2-Profile/SWORDProfile.html#protocoloperations_listingcollections
- Consistent with the format in state.xml and deposit_receipt.xml
- Avoids introducing a new tag
Related to #2996 (closed)
Migrated from D5779 (view on Phabricator)