Fix main binary being rebuilt when nothing has changed (#13337)

# Description
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The build script is currently re-run on each `cargo build` even when it
has not changed. The `rerun-if-changed` line points to `/build.rs`, but
`build.rs` is actually located at `/scripts/build.rs`. This updates that
path.

# User-Facing Changes
N/A

# Tests + Formatting
N/A

scripts/build.rs

@@ -14,5 +14,5 @@ fn main() {
     // Tango uses dynamic linking, to allow us to dynamically change between two bench suit at runtime.
     // This is currently not supported on non nightly rust, on windows.
     println!("cargo:rustc-link-arg-benches=-rdynamic");
-    println!("cargo:rerun-if-changed=build.rs");
+    println!("cargo:rerun-if-changed=scripts/build.rs");
 }