Remove "Sort by relevance" option on Bookmarks page

[maxkadel]

User story

As a user, all items I have bookmarked are equally relevant to me, so a sort by relevance is meaningless.

Acceptance criteria

• The default sort on the /bookmarks page is by title
• The 'relevance' sort option does not appear on the /bookmarks page
• The 'relevance' sort option is still the default for catalog searches

Implementation notes, if any

• You can decide whether a sort option is displayed or not using if: or unless: configuration options with a lambda or proc
• You can mark a field as the default sort using default: true (otherwise I believe it uses the first sort field int he config). I do not believe you can use a lambda or proc for the default field configuration. This may need to be an added feature in Blacklight to do this ticket.

[ellen-aa]

@maxkadel PO-priority label added! I think sort by title makes good sense.