Merge pull request #87 from danielparks/dockerfile-fix

Dockerfile: Remove CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse and fix ENV line.

Author: danielparks

Dockerfile

@@ -7,10 +7,7 @@ RUN apt-get update \
   && apt-get install -y locales curl valgrind build-essential \
   && rm -rf /var/lib/apt/lists/* \
 	&& localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8
-ENV LANG en_US.utf8
-
-# Remove after Rust 1.70 when this becomes default
-ENV CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse
+ENV LANG=en_US.utf8
 
 # Install rustup, rust, and cargo-binstall
 RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \