ARROW-14489: [Rust][CI] Install stable rust toolchain in the integrat…

…ion docker image

otherwise [downstream pull request][1] will be blocked at 1.55 rust version

[1]: apache/arrow-rs#591

Closes #11557 from Jimexist/update-conda-integration

Lead-authored-by: Jiayu Liu <jiayu.liu@airbnb.com>
Co-authored-by: Krisztián Szűcs <szucs.krisztian@gmail.com>
Signed-off-by: Krisztián Szűcs <szucs.krisztian@gmail.com>

ci/docker/conda-integration.dockerfile

@@ -40,6 +40,7 @@ RUN conda install -q \
 # Install Rust with only the needed components
 # (rustfmt is needed for tonic-build to compile the protobuf definitions)
 RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --profile=minimal -y && \
+    $HOME/.cargo/bin/rustup toolchain install stable && \
     $HOME/.cargo/bin/rustup component add rustfmt
 
 ENV GOROOT=/opt/go \
@@ -51,7 +52,7 @@ RUN wget -nv -O - https://dl.google.com/go/go${go}.linux-${arch}.tar.gz | tar -x
 ENV DOTNET_ROOT=/opt/dotnet \
     PATH=/opt/dotnet:$PATH
 RUN curl -sSL https://dot.net/v1/dotnet-install.sh | bash /dev/stdin -Channel 3.1 -InstallDir /opt/dotnet
-    
+
 ENV ARROW_BUILD_INTEGRATION=ON \
     ARROW_BUILD_STATIC=OFF \
     ARROW_BUILD_TESTS=OFF \