Update Dockerfile

Dockerfile

@@ -10,14 +10,11 @@ RUN apt-get update && apt-get upgrade -y && apt-get install -y --no-install-reco
     gnupg2 \
     wget
 
-# Add PPA for gcc-11, update packages, install gcc-11, g++-11, update pip and setuptools, install build-essential
-RUN add-apt-repository ppa:ubuntu-toolchain-r/test
 RUN apt update
 RUN apt install gcc-11 g++-11
 RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 60 --slave /usr/bin/g++ g++ /usr/bin/g++-11
 RUN pip install --upgrade pip
 RUN pip install --upgrade setuptools wheel
-RUN apt-get install build-essential
 
 WORKDIR /code