ci(dist-aarch64-linux): preload built libstdc++

Just like what we did for x86_64 in PR 134690

src/ci/docker/host-aarch64/dist-aarch64-linux/Dockerfile

diff --git a/src/ci/docker/host-aarch64/dist-aarch64-linux/Dockerfile b/src/ci/docker/host-aarch64/dist-aarch64-linux/Dockerfile
index 1e205aa..88f81e5 100644
--- a/src/ci/docker/host-aarch64/dist-aarch64-linux/Dockerfile
+++ b/src/ci/docker/host-aarch64/dist-aarch64-linux/Dockerfile
@@ -101,3 +101,7 @@
 ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=clang
 ENV LIBCURL_NO_PKG_CONFIG="1"
 ENV DIST_REQUIRE_ALL_TOOLS="1"
+
+# FIXME: Without this, LLVMgold.so incorrectly resolves to the system
+# libstdc++, instead of the one we build.
+ENV LD_PRELOAD=/rustroot/lib64/libstdc++.so.6