Fix fuzzer build by using mold (#9909)

Instrumented binaries had jump offsets that exceed default linker
support. Mold should handle this just fine

Signed-off-by: Robert Kruszewski <github@robertk.io>

Author: robert3005

.github/scripts/build-fuzzers.sh

@@ -6,6 +6,11 @@ set -euo pipefail
 
 mkdir -p fuzz-binaries
 
+if [[ "$(uname -s)" == Linux ]]; then
+  # Use mold to handle long-range calls in the instrumented ARM64 binaries.
+  export RUSTFLAGS="${RUSTFLAGS:-} -C link-arg=-fuse-ld=mold"
+fi
+
 cargo "+$NIGHTLY_TOOLCHAIN" fuzz build --release --debug-assertions
 
 copy_fuzzer() {