Change path to zld on MacOS fast build example (#4778)

# Objective
Fixes #4751, zld link error.

## Solution

- Change the `zld` file path in the example to the one homebrew installs to by default, `/usr/local/bin/zld`.

Author: Matt Wilkinson

.cargo/config_fast_builds

@@ -10,7 +10,7 @@ rustflags = ["-Clink-arg=-fuse-ld=lld", "-Zshare-generics=y"]
 # NOTE: you must manually install https://github.com/michaeleisel/zld on mac. you can easily do this with the "brew" package manager:
 # `brew install michaeleisel/zld/zld`
 [target.x86_64-apple-darwin]
-rustflags = ["-C", "link-arg=-fuse-ld=/opt/homebrew/bin/zld", "-Zshare-generics=y"]
+rustflags = ["-C", "link-arg=-fuse-ld=/usr/local/bin/zld", "-Zshare-generics=y"]
 
 [target.aarch64-apple-darwin]
 rustflags = ["-C", "link-arg=-fuse-ld=/opt/homebrew/bin/zld", "-Zshare-generics=y"]