build: Update Rubocop config for deprecations
build: Update Rubocop config for deprecations

They renamed a bunch of options and it's printing warnings now.

Also, add `Layout/EndOfLine: EnforcedStyle: lf`, otherwise it
apparently guesses the expected end-of-line format based on the
operating system (?????) and fails the lint check for me locally.

Change-Id: Ie39b09e0f6e3789dfb767a88dda4d9ea8641d5cc

wikimedia/oojs-ui,wikimedia/oojs-ui,wikimedia/oojs-ui,wikimedia/oojs-ui