[fix] benchmark run with compose (#666)

Author: rdettai

benchmarks/README.md

@@ -140,7 +140,7 @@ docker-compose up
 Then you can run the benchmark with:
 
 ```bash
-docker-compose run ballista-client cargo run benchmark ballista --host ballista-scheduler --port 50050 --query 1 --path /data --format tbl
+docker-compose run ballista-client bash -c '/tpch benchmark ballista --host ballista-scheduler --port 50050 --query 1 --path /data --format tbl'
 ```
 
 ## Expected output

benchmarks/docker-compose.yaml

@@ -41,12 +41,10 @@ services:
   ballista-client:
     image: ballista:0.5.0-SNAPSHOT
     command: "/bin/sh" # do nothing
-    working_dir: /ballista/benchmarks/tpch
     environment:
       - RUST_LOG=info
     volumes:
       - ./data:/data
-      - ../..:/ballista
     depends_on:
       - ballista-scheduler
       - ballista-executor