Tighten our rules in our entitlements file for macOS

comment:40:ticket:30126 mentions two possible rules we could tighten in our entitelments file:

com.apple.security.cs.disable-library-validation=false com.apple.security.automation.apple-events=false

The former seems indeed to be a clear winner but I am not sure about the latter as we usually don't want to break the expected behavior for users installing WebExtensions (even if we don't recommend it).

We could think about more rules to be tightened while we are at it.