sanitizer.md: LeakSanitizer is not supported on aarch64 macOS

Author: radiohertz

src/doc/unstable-book/src/compiler-flags/sanitizer.md

@@ -690,7 +690,6 @@ LeakSanitizer is run-time memory leak detector.
 
 LeakSanitizer is supported on the following targets:
 
-* `aarch64-apple-darwin`
 * `aarch64-unknown-linux-gnu`
 * `x86_64-apple-darwin`
 * `x86_64-unknown-linux-gnu`