Warning caused by preinstalled p7zip on macOS

[ltoenning]

From these lines:

https://github.com/jurplel/install-qt-action/blob/0fe81f805e5f2d6d4e45809cb9d20822e6c81b2d/action/src/main.ts#L347-L350

we are getting the following warning when running on macos-12:

/usr/local/bin/brew install p7zip
Warning: p7zip 17.05 is already installed and up-to-date.
To reinstall 17.05, run:
  brew reinstall p7zip
Warning: p7zip 17.05 is already installed and up-to-date.
To reinstall 17.05, run:
  brew reinstall p7zip

This triggers a warning annotation for the entire job.

It seems that 7zip is (now) preinstalled: https://github.com/actions/runner-images/blob/main/images/macos/macos-11-Readme.md#utilities