Remove left-over parameter (#1578)

Removes accidentially forgotten parameter, fixing the prefetcher and
client benchmarks to be executable again.


---

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Signed-off-by: Christian Hagemeier <chagem@amazon.com>

Author: c-hagem

benchmark/benchmarks/client_benchmark.py

@@ -81,7 +81,7 @@ def get_command(self) -> Command:
 
         log.info("Client benchmark command prepared with args: %s", subprocess_args)
 
-        return Command(args=subprocess_args, env=client_env, capture_output=True)
+        return Command(args=subprocess_args, env=client_env)
 
     def post_process(self, result: CommandResult) -> Dict[str, Any]:
         if result.returncode != 0:

benchmark/benchmarks/prefetch_benchmark.py

@@ -78,7 +78,7 @@ def get_command(self) -> Command:
 
         log.info("Prefetch benchmark command prepared with args: %s", subprocess_args)
 
-        return Command(args=subprocess_args, env=prefetch_env, capture_output=True)
+        return Command(args=subprocess_args, env=prefetch_env)
 
     def post_process(self, result: CommandResult) -> Dict[str, Any]:
         if result.returncode != 0: