docker: fix rustup
@@ -154,4 +154,4 @@ RUN virtualenv "${COVERALLS_VIRTUALENV_PATH}" \
ENV PATH="${PATH}:${COVERALLS_VIRTUALENV_PATH}/bin"
# rust
-curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -y
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y -q
