CI/Rust: remove nightly version requirements

dockerfiles/stages/1-build-deps

@@ -24,9 +24,6 @@ ARG GO_CAPNP_VERSION=v3.0.0-alpha.5
 # - src/lib/crypto/kimchi_bindings/stubs/rust-toolchain.toml
 # - src/lib/crypto/proof-systems/rust-toolchain.toml
 ARG RUST_VERSION=1.72
-# Nightly Rust Version used for WebAssembly builds
-# - src/lib/crypto/kimchi_bindings/wasm/rust-toolchain.toml
-ARG RUST_NIGHTLY=2023-09-01
 # wasm-pack version
 ARG WASM_PACK_VERSION=v0.12.1
 
@@ -97,7 +94,6 @@ RUN curl -sL \
 RUN curl -s "https://dl.google.com/go/go${GO_VERSION}.linux-amd64.tar.gz" | tar -xz -C /usr/lib/
 
 # --- Rust install via rustup-init to a given RUST_VERSION
-# --- Additionally, install RUST_NIGHTLY via rustup
 # For more about rustup-init see: https://github.com/rust-lang/rustup/blob/master/README.md
 # As opposed to introducing another shell script here (that mostly just determines the platform)
 # we just download the binary for the only platform we care about in this docker environment
@@ -106,7 +102,6 @@ RUN curl --proto '=https' --tlsv1.2 -sSf -o /tmp/rustup-init \
   https://static.rust-lang.org/rustup/dist/x86_64-unknown-linux-gnu/rustup-init \
   && chmod +x /tmp/rustup-init \
   && /tmp/rustup-init -y --default-toolchain "${RUST_VERSION}" --profile minimal --component rust-src --target wasm32-unknown-unknown \
-  && $HOME/.cargo/bin/rustup toolchain install "nightly-${RUST_NIGHTLY}" --profile minimal --component rust-src --target wasm32-unknown-unknown --no-self-update \
   && rm /tmp/rustup-init
 USER root