Build fails: "cannot create regular file"

[samestep]

After applying the typo fixes from #3 I ran the command

python3 pochivm-build cmake debug

and it seems to have successfully built the Docker image, but then failed with this error:

Docker image 'pochivm-build:latest' does not exist.
Building docker image, this may take a while...
[+] Building 351.9s (18/18) FINISHED                                                          docker:default
 => [internal] load build definition from Dockerfile                                                    0.0s
 => => transferring dockerfile: 766B                                                                    0.0s
 => [internal] load metadata for docker.io/library/ubuntu:18.04                                         0.6s
 => [internal] load .dockerignore                                                                       0.0s
 => => transferring context: 2B                                                                         0.0s
 => [ 1/13] FROM docker.io/library/ubuntu:18.04@sha256:152dc042452c496007f07ca9127571cb9c29697f42acbfa  2.1s
 => => resolve docker.io/library/ubuntu:18.04@sha256:152dc042452c496007f07ca9127571cb9c29697f42acbfad7  0.0s
 => => sha256:7c457f213c7634afb95a0fb2410a74b7b5bc0ba527033362c240c7a11bef4331 25.69MB / 25.69MB        0.6s
 => => extracting sha256:7c457f213c7634afb95a0fb2410a74b7b5bc0ba527033362c240c7a11bef4331               1.4s
 => [internal] load build context                                                                       0.1s
 => => transferring context: 95B                                                                        0.0s
 => [ 2/13] RUN apt update && apt install -y git wget tar xz-utils sudo cmake make ninja-build python  51.5s
 => [ 3/13] RUN apt update && apt-get install -y g++ libtinfo-dev                                       7.7s 
 => [ 4/13] RUN wget -O llvm.tar.xz https://github.com/llvm/llvm-project/releases/download/llvmorg-10  10.6s 
 => [ 5/13] RUN tar xf llvm.tar.xz                                                                     52.3s 
 => [ 6/13] RUN cp -r clang+llvm-10.0.0-x86_64-linux-gnu-ubuntu-18.04/* /usr/local/                     7.8s 
 => [ 7/13] RUN rm -rf clang+llvm-10.0.0-x86_64-linux-gnu-ubuntu-18.04                                  0.5s 
 => [ 8/13] RUN rm -f llvm.tar.xz                                                                       0.4s 
 => [ 9/13] RUN useradd -ms /bin/bash u                                                                 0.6s 
 => [10/13] RUN usermod -aG sudo u                                                                      0.4s 
 => [11/13] RUN echo 'u ALL=(ALL) NOPASSWD:ALL' >> /etc/sudoers                                         0.4s
 => [12/13] COPY ccache.conf /etc/ccache.conf                                                           0.2s
 => [13/13] WORKDIR /home/u                                                                             0.1s
 => exporting to image                                                                                214.1s
 => => exporting layers                                                                               166.5s
 => => exporting manifest sha256:2a63116ad2c92e4415866d2397d30d4982408892af406818ce928d22b3859c5a       0.0s
 => => exporting config sha256:cbaaa4497565548af03ba05dcdc75d14ba9cd915e1d86319d2f6b5607aa9d90e         0.0s
 => => exporting attestation manifest sha256:6f4b3474ae1494fd06e3a17ef0384c900322d03c567414808f113fe1d  0.1s
 => => exporting manifest list sha256:9d6142de524a0be4544669bcecc76454042c105fbdf5c396e0e19f4147efe103  0.0s
 => => naming to docker.io/library/pochivm-build:latest                                                 0.0s
 => => unpacking to docker.io/library/pochivm-build:latest                                             47.3s
cp: cannot create regular file '/home/u/PochiVM/shared_libs/libtinfo.so.5': Permission denied
[ERROR] Failed to copy shared library /lib/x86_64-linux-gnu/libtinfo.so.5, exit code = 256