Don't display the dev warning time when running self-update

Use the Application::find() method to resolve the command name, as Application::getCommandName() only returns whatever was entered as the first argument.
If the user only entered enough of the command to be unambiguous (eg self-up) then the warning would still show
By calling Application::find() we ensure that if we are going to run the self-update command then we will not show the warning, no matter what the user entered

The previous attempts to solve this problem:
2448c5a7c273b347d2dce568c30fb5bb31a269fa
390ac65466121ba2205d8d97f2b25c5fbdc874e8