feat(devcontainer): supersede zephyr-west-action-arm with zmk-dev-arm

PR: #481

.devcontainer/Dockerfile

@@ -1,15 +1,4 @@
-FROM zmkfirmware/zephyr-west-action-arm
+FROM zmkfirmware/zmk-dev-arm:2.3
-
-ENV LC_ALL=C
-
-RUN apt-get -y update && \
-    apt-get -y upgrade && \
-    apt-get install --no-install-recommends -y \
-    ssh \
-    nano \
-    locales \
-    gpg && \
-    rm -rf /var/lib/apt/lists/*
 
 COPY .bashrc tmp
 RUN mv /tmp/.bashrc ~/.bashrc