ci: install g++ for cross build (#10932)

Author: everpcpc

docker/build-tool/gnu/Dockerfile

@@ -4,7 +4,7 @@ FROM datafuselabs/build-tool:base-${RUST_TOOLCHAIN}
 ENV PKG_CONFIG_ALLOW_CROSS 1
 RUN dpkg --add-architecture arm64 && \
     apt-get update -yq && \
-    apt-get install -yq libc6-arm64-cross libc6-dev-arm64-cross gcc-aarch64-linux-gnu && \
+    apt-get install -yq libc6-arm64-cross libc6-dev-arm64-cross gcc-aarch64-linux-gnu g++-aarch64-linux-gnu && \
     apt-get install -yq libdbus-1-dev libdbus-1-dev:arm64 && \
     apt-get install -yq libssl-dev libssl-dev:arm64 zlib1g-dev zlib1g-dev:arm64
 

docker/build-tool/musl/Dockerfile

@@ -25,5 +25,6 @@ RUN curl -sSfLo /tmp/musl-cross-make.tar.gz https://github.com/richfelker/musl-c
 ENV je_cv_pthread_getname_np no
 ENV C_INCLUDE_PATH /usr/local/${ARCH}-linux-musl/include/
 RUN ln -s ${ARCH}-linux-musl-gcc /usr/local/bin/musl-gcc
+RUN ln -s ${ARCH}-linux-musl-g++ /usr/local/bin/musl-g++
 RUN rustup target add ${ARCH}-unknown-linux-musl
-RUN printf "[target.${ARCH}-unknown-linux-musl]\nlinker = \"${ARCH}-linux-musl-gcc\"\n" > ${CARGO_HOME}/config
+RUN printf "[target.${ARCH}-unknown-linux-musl]\nlinker = \"${ARCH}-linux-musl-gcc\"\n" >${CARGO_HOME}/config