MERC-691: revert back to slick-carousel v1.5.5
MERC-691: revert back to slick-carousel v1.5.5

fix for missing previous slide arrow on the carousel. v1.5.6 of the lib introduced a change to the dom location of the arrow, causing the z-index to be lower than the carousel image.

ovsokolov/dashconnect-bc,aaronrodier84/rouxbrands,mcampa/cornerstone,PascalZajac/cornerstone,juancho1/bauhaus,caras-ey/BST,ovsokolov/dashconnect-bc,PascalZajac/cornerstone,mcampa/cornerstone,PascalZajac/cornerstone,aaronrodier84/flukerfarms,rho1140/cornerstone,bigcommerce/stencil,PeteyRev/ud-revamp,ovsokolov/dashconnect-bc,mcampa/cornerstone,rho1140/cornerstone,bc-annavu/stencil,caras-ey/BST,aaronrodier84/rouxbrands,aaronrodier84/flukerfarms,PeteyRev/ud-revamp,PeteyRev/ud-revamp,juancho1/bauhaus,rho1140/cornerstone,juancho1/bauhaus,aaronrodier84/flukerfarms,bc-annavu/stencil,caras-ey/BST,bigcommerce/stencil,aaronrodier84/rouxbrands,bigcommerce/stencil,bc-annavu/stencil