[red-knot] update benchmark to run on tomllib (#12635)

Changes the red-knot benchmark to run on the stdlib "tomllib" library
(which is self-contained, four files, uses type annotations) instead of
on very small bits of handwritten code.

Also remove the `without_parse` benchmark: now that we are running on
real code that uses typeshed, we'd either have to pre-parse all of
typeshed (slow) or find some way to determine which typeshed modules
will be used by the benchmark (not feasible with reasonable complexity.)

## Test Plan

`cargo bench -p ruff_benchmark --bench red_knot`

crates/ruff_benchmark/src/lib.rs

@@ -70,6 +70,16 @@ pub struct TestFile {
     code: String,
 }
 
+impl TestFile {
+    pub fn code(&self) -> &str {
+        &self.code
+    }
+
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+}
+
 static TARGET_DIR: once_cell::sync::Lazy<PathBuf> = once_cell::sync::Lazy::new(|| {
     cargo_target_directory().unwrap_or_else(|| PathBuf::from("target"))
 });
@@ -114,7 +124,7 @@ impl TestFile {
             // SAFETY: There's always the `target` directory
             let parent = cached_filename.parent().unwrap();
             if let Err(error) = std::fs::create_dir_all(parent) {
-                eprintln!("Failed to crate the directory for the test case {name}: {error}");
+                eprintln!("Failed to create the directory for the test case {name}: {error}");
             } else if let Err(error) = std::fs::write(cached_filename, &content) {
                 eprintln!("Failed to cache test case file downloaded from {url}: {error}");
             }