item: add request on item by librarian

[Garfield-fr]

Co-Authored-by: Bertrand Zuchuat [email protected]

Why are you opening this PR?

• to add request functionality on item by the librarian

How to test?

• Dependency: requests: place a request for a patron by a librarian rero-ils#835
• Test "new request" on item (document detail view)
• Several cases where the request can't be performed can be tested:
  • invalid patron barcode
  • an item can't be requested due to the circulation policies (for ex. with a specific item_type)
  • the item has been already requested by the same patron

Screenshots

Code review check list

• Commit message template compliance.
• Commit message without typos.
• File names.
• Functions names.
• Functions docstrings.
• Unnecessary commited files?
• Extracted translations?