Disable Rubocop task when Rubocop gem is unavailable to fix issue in production
Disable Rubocop task when Rubocop gem is unavailable to fix issue in production

Signed-off-by: Theo Cushion <9391e8fee6b4bb857269a4f82fb270f1b8927974@pivotal.io>

FundingCircle/shipment_tracker,iainbeeston/shipment_tracker,iainbeeston/shipment_tracker,FundingCircle/shipment_tracker,FundingCircle/shipment_tracker,iainbeeston/shipment_tracker,FundingCircle/shipment_tracker,iainbeeston/shipment_tracker