docker esp32: fix failing builds on linux

when building with mos build, the docker container is called with the
current userid on the host, which might not necessarily exist within the
docker container. The folder of the 'user' (/opt/Espressif) needs to be
accessed in the build by this other user, but cannot, as the permission
on useradd is set to 0 for others. This works around the issue by
extending the permissions for other users

Author: markirb

tools/docker/esp32/Dockerfile-esp32-build

@@ -19,7 +19,7 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
       python2 python2-dev && \
     apt-get clean
 
-RUN useradd -d /opt/Espressif -m -s /bin/bash user && chown -R user /opt
+RUN useradd -d /opt/Espressif -m -s /bin/bash user && chmod o+rx /opt/Espressif
 
 ARG TARGETARCH
 ARG TOOLCHAIN_URLS="https://github.com/espressif/crosstool-NG/releases/download/esp-2021r2-patch3/xtensa-esp32-elf-gcc8_4_0-esp-2021r2-patch3-linux-${TARGETARCH}.tar.gz https://github.com/espressif/crosstool-NG/releases/download/esp-2021r2-patch3/riscv32-esp-elf-gcc8_4_0-esp-2021r2-patch3-linux-${TARGETARCH}.tar.gz https://github.com/espressif/crosstool-NG/releases/download/esp-2021r2-patch3/xtensa-esp32s3-elf-gcc8_4_0-esp-2021r2-patch3-linux-${TARGETARCH}.tar.gz"