Fixed Docker builds

Dockerfile

@@ -1,14 +1,22 @@
-FROM ubuntu:20.04 as build
-
+FROM ubuntu:20.04 AS build
 ENV DEBIAN_FRONTEND=noninteractive
 
-COPY packages.txt /
-RUN apt-get update && apt-get install -y $(cat packages.txt)
+# (for debug purposes)
+RUN echo "System arch: $(uname -a)\nDPKG arch: $(dpkg --print-architecture)"
 
-RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
+# Install package dependencies
+COPY packages.txt ./
+RUN apt-get update && apt-get install -y $(cat packages.txt) && rm packages.txt
 
-COPY requirements.txt /
+# Install Rust/Cargo
+# NOTE: We replace /proc/self/exe with /bin/sh in the script to avoid issues with Docker
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sed 's#/proc/self/exe#\/bin\/sh#g' | CARGO_HOME=/opt/cargo sh -s -- -y
+ENV PATH=/opt/cargo/bin:$PATH
+
+# Install Python dependencies
+COPY requirements.txt ./
+COPY tools/n64splat/requirements.txt ./tools/n64splat/requirements.txt
 RUN python3 -m pip install -r requirements.txt
 
-RUN mkdir /banjo
 WORKDIR /banjo
+ENTRYPOINT ["/bin/bash", "-c"]