documentation

[ZBXNEXT-8783] added API changes for connectors about item_value_type and attempt_interval

* commit 'bb210120b61d20aabbaef529819c98ad75563373':
  [ZBXNEXT-8783] fixed ordering
  [ZBXNEXT-8783] fixed ordering in connector.get example
  [ZBXNEXT-8783] added missing spaces and improved formating of item_value_type and attempt_interval in connector.object
  [ZBXNEXT-8783] added missing comma in API changes related to connector
  [ZBXNEXT-8783] changed tabs to spaces
  [ZBXNEXT-8783] added API changes in connector about item_value_type and attempt_interval