documentation

[ZBX-21804] removed requirement for write permissions on hosts, host groups, triggers, discovery rules, discovery checks and proxies when creating or updating actions

Merge in WEB/documentation from feature/ZBX-21804-6.0-D to release/6.0

* commit 'c4c17e9bca5a443bf96477157fd004689c98effd':
  .......... [ZBX-21804] removed editable from supported action.get options
  A.F....... [ZBX-21804] removed newline
  A.F....... [ZBX-21804] updated api changes page