fix(dockerfile): install coreutils to resolve timeout command error (#1260)

Author: utsab345

rdagent/scenarios/qlib/docker/Dockerfile

@@ -7,6 +7,7 @@ RUN apt-get clean && apt-get update && apt-get install -y \
     vim \  
     git \  
     build-essential \
+    coreutils \
     && rm -rf /var/lib/apt/lists/* 
 
 RUN git clone https://github.com/microsoft/qlib.git