Don't unnecessarily load bundler in rakefile.
Don't unnecessarily load bundler in rakefile.

This allows --standalone to be used instead.
cemo/vcr,allyapp/vcr,mcfiredrill/vcr,Shopify/vcr,irfanah/vcr,ZmagoD/vcr,cemo/vcr,nishanbose/vcr,irfanah/vcr,ihassin/vcr,ZmagoD/vcr,Shopify/vcr,chriswoodrich/vcr,davidbebb/vcr,nishanbose/vcr,intfrr/vcr,chriswoodrich/vcr,intfrr/vcr,asymmetric/vcr,asymmetric/vcr,allyapp/vcr,davidbebb/vcr,mcfiredrill/vcr,ihassin/vcr