integration_tests: abort when rustup install fails

When there is an error fetching the script and the result is empty, bash does not complain. The result is an undetected broken image.

Signed-off-by: Simon Brand <simon.brand@postadigitale.de>

Author: brandsimon

tss-esapi/tests/Dockerfile-ubuntu

@@ -2,7 +2,7 @@ FROM ghcr.io/tpm2-software/ubuntu-20.04:latest AS base
 
 FROM base AS rust-toolchain
 # Install Rust toolchain
-RUN curl https://sh.rustup.rs -sSf | bash -s -- -y
+RUN (curl https://sh.rustup.rs -sSf || exit 1) | bash -s -- -y
 ENV PATH="/root/.cargo/bin:${PATH}"
 
 FROM rust-toolchain AS tpm2-tss