RFR: 8303130: Document required Accessibility permissions on macOS [v3]

[Dmitry Markov]

> Added the section devoted to client UI test which use Robot API

Dmitry Markov has updated the pull request incrementally with one additional commit since the last revision:

  Fix typo

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12772/files
  - new: https://git.openjdk.org/jdk/pull/12772/files/e1ec5f9e..1ce9b932

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12772&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12772&range=01-02

  Stats: 4 lines in 2 files changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/12772.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12772/head:pull/12772

PR: https://git.openjdk.org/jdk/pull/12772