Issue 2974: Update the docker-compose yml link in the documentation (#2964)
Issue 2974: Update the docker-compose yml link in the documentation (#2964)

* Updates current link to point to the raw file.

Signed-off-by: Mehdi <dfc3834ad6b2e23bb1797b92b0f83bc1bc55b1b3@salesforce.com>
pravega/pravega,pravega/pravega,pravega/pravega