specify arm64 arch

Author: Steve Lee (POWERSHELL HE/HIM) (from Dev Box)

.pipelines/DSC-Official.yml

@@ -323,7 +323,8 @@ extends:
             $env:CC_aarch64_unknown_linux_musl='clang'
             $env:AR_aarch64_unknown_linux_musl='llvm-ar'
             $env:CARGO_TARGET_AARCH64_UNKNOWN_LINUX_MUSL_RUSTFLAGS="-Clink-self-contained=yes -Clinker=rust-lld"
-            apt update
+            dpkg --add-architecture arm64
+            apt update -o APT::Architecture="arm64" -o APT::Architectures="arm64"
             apt -y install clang
             apt -y install llvm
             apt -y install musl-tools