chore: remove mentions to old runtime variable

docs/execution_walkthrough.md

@@ -206,7 +206,7 @@ Builtin stats: BuiltinStats { bitwise: 1, ec_op: 0, range_check: 1, pedersen: 0,
 ## The Cairo Native runtime
 Sometimes we need to use stuff that would be too complicated or error-prone to implement in MLIR, but that we have readily available from Rust. That's when we use the runtime library.
 
-When using the JIT it'll be automatically linked (if compiled with support for it, which is enabled by default). If using the AOT, the `CAIRO_NATIVE_RUNTIME_LIBDIR` environment variable will have to be modified to point to the directory that contains `libcairo_native_runtime.a`, which is built and placed in said folder by `make build`.
+When using the JIT it'll be automatically linked (if compiled with support for it, which is enabled by default). If using the AOT, the `CAIRO_NATIVE_RUNTIME_LIBRARY` environment variable will have to be modified to point to the `libcairo_native_runtime.a` file, which is built and placed in said folder by `make build`.
 
 Although it's implemented in Rust, its functions use the C ABI and have Rust's name mangling disabled. This means that to the extern observer it's technically indistinguishible from a library written in C. By doing this we're making the functions callable from MLIR.
 

scripts/bench-hyperfine.sh

@@ -90,7 +90,7 @@ run_bench() {
         -o "$OUTPUT_DIR/$base_name-march-native" \
         >> /dev/stderr
 
-    CAIRO_NATIVE_RUNTIME_LIBDIR="$ROOT_DIR/target/release" hyperfine \
+     hyperfine \
         --warmup 3 \
         --export-markdown "$OUTPUT_DIR/$base_name.md" \
         --export-json "$OUTPUT_DIR/$base_name.json" \