Fix project root assert

Signed-off-by: hi-rustin <rustin.liu@gmail.com>

crates/sourcegen/src/lib.rs

@@ -196,6 +196,6 @@ fn normalize_newlines(s: &str) -> String {
 pub fn project_root() -> PathBuf {
     let dir = env!("CARGO_MANIFEST_DIR");
     let res = PathBuf::from(dir).parent().unwrap().parent().unwrap().to_owned();
-    assert!(res.join("bors.toml").exists());
+    assert!(res.join("triagebot.toml").exists());
     res
 }