documentation

Pull request #4581: Feature/DEV-4968 7.5 D

Merge in WEB/documentation from feature/DEV-4968-7.5-D to release/8.0

* commit 'c91f73fd6bb1ff39eab1098225d3354ddf2f2755':
  [DEV-4968] updated Known issues entry
  [DEV-4968] updated description
  [DEV-4968] updated formatting
  [DEV-4968] improved wording
  [DEV-4968] documented known MySQL issue