SDC-1691 - Dockerfile is looking for tar file not tgz file
SDC-1691 - Dockerfile is looking for tar file not tgz file

Change-Id: I2dbacaba90e77ff311682f372cb279e5cf89fa75
Reviewed-on: https://review.streamsets.net/1205
Reviewed-by: Adam Kunicki <0e18f44c1fec03ec4083422cb58ba6a09ac4fb2a@streamsets.com>
Tested-by: StreamSets CI <809627f37325a679986bd660c7713476a56d59cd@streamsets.com>

streamsets/datacollector,kunickiaj/datacollector,kunickiaj/datacollector,kunickiaj/datacollector,SandishKumarHN/datacollector,SandishKumarHN/datacollector,studanshu/datacollector,kiritbasu/datacollector,rockmkd/datacollector,z123/datacollector,studanshu/datacollector,kiritbasu/datacollector,kiritbasu/datacollector,WgStreamsets/datacollector,studanshu/datacollector,WgStreamsets/datacollector,rockmkd/datacollector,streamsets/datacollector,z123/datacollector,kunickiaj/datacollector,z123/datacollector,kiritbasu/datacollector,studanshu/datacollector,WgStreamsets/datacollector,kunickiaj/datacollector,rockmkd/datacollector,streamsets/datacollector,streamsets/datacollector,streamsets/datacollector,rockmkd/datacollector,rockmkd/datacollector,SandishKumarHN/datacollector,kiritbasu/datacollector,WgStreamsets/datacollector,SandishKumarHN/datacollector,WgStreamsets/datacollector,SandishKumarHN/datacollector,z123/datacollector,z123/datacollector,studanshu/datacollector