Install riscv-gnu-toolchain and riscof in Dockerfile

.github/actions/with-docker/Dockerfile

@@ -1,6 +1,10 @@
 ARG K_VERSION
 FROM runtimeverificationinc/kframework-k:ubuntu-jammy-${K_VERSION}
 
+ARG TOOLCHAIN_VERSION
+FROM runtimeverificationinc/riscv-gnu-toolchain:ubuntu-jammy-${TOOLCHAIN_VERSION} as TOOLCHAIN
+COPY --from=TOOLCHAIN /opt/riscv/bin /home/user/riscv/bin
+
 ARG PYTHON_VERSION=3.10
 
 RUN    apt-get -y update             \
@@ -20,3 +24,7 @@ WORKDIR /home/user
 
 ENV PATH=/home/user/.local/bin:${PATH}
 RUN curl -sSL https://install.python-poetry.org | python3 -
+
+ENV PATH=/home/user/riscv/bin:${PATH}
+
+RUN pip3 install git+https://github.com/riscv/riscof.git