@WMDE-leszek placeholder

The same approach to be used as for GET routes for statements
MW OAuth provided bearder token authorization to be used with Authorization HTTP request header, and X-Authenticated-User header in the responses.

GET /entities/items/{item_id}/labels
GET /entities/items/{item_id}/labels/{language_code}
GET /entities/items/{item_id}/descriptions
GET /entities/items/{item_id}/descriptions/{language_code}
GET /entities/items/{item_id}/aliases
GET /entities/items/{item_id}/aliases/{language_code}