Merge topic 'ci-xcode-12.2' into release-3.19

5213328008 gitlab-ci: update macOS jobs to use Xcode 12.2
928ca50b6f Tests: Teach RunCMake to ignore Xcode install_name_tool signature warnings

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !5534