Search for nginx folder based on CARGO_MANIFEST_DIR

nginx_module/build.rs

@@ -96,8 +96,9 @@ fn search_nginx_root_folder() -> String {
 
     // First, try to find the include folders in any of the parent folders of this folder,
     // This is the case when this is a submodule of nginx
+    let manifest_dir = env!("CARGO_MANIFEST_DIR");
     for base in base_locations {
-        let folder = base.to_string();
+        let folder = format!("{manifest_dir}/{base}");
         if check_nginx_root(Path::new(&folder)) {
             return folder;
         }