PhutilConsole->confirm() is vestigial as noted in efcd70c, as
PhutilConsole may be deprecated sometime in the future. PhutilConsole
was developed as a tool for T4281 but the feature has been removed
since.
Replace existing occurences of the PhutilConsole->confirm() pattern with
phutil_console_confirm(). There should be no change in functionality
since the two functions are interchangeable.