Update Dockerfile

[JustinMoorcroft]

The name of the link from /var/scan/node_modules/.bin has changed to cloudsploitscan At the moment, when trying to run the docker container, docker throws an error complaining about cloudsploit-scan not being in the PATH I did some debugging (just installed bash in the image build, and exec'd in to look around) and saw that the name had changed - and now the docker container runs

[CLAassistant]

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