Update awscli blobs to use python3
Update awscli blobs to use python3

- we replaced python with python3 in newer versions of stemcell.

[#163965559](https://www.pivotaltracker.com/story/show/163965559)

Co-authored-by: Gaurab Dey <6eab2c4141d8485c934adabfb0522546caded7e6@pivotal.io>

cloudfoundry-incubator/bosh-aws-cpi-release,cloudfoundry-incubator/bosh-aws-cpi-release,cloudfoundry-incubator/bosh-aws-cpi-release