Don't always try to add Approved label to chromedriver executable on macOS

[DaniruKun]

One of the mechanisms used to make sure that after an upgrade, chromedriver is still allowed to run without requiring to manually allow it in Settings is by setting the right label with spctl:

 spctl --add --label 'Approved' $(which chromedriver)

However, there isn't really an obvious way to check if the label is already placed on the executable (especially without annoying the user for Touch ID).

An idea could be to check if the checksum of the chromedriver installation has changed, and only then run the quarantine removal + spctl.