message: try to fix build failure in docs.rs
diff: @@ -55,6 +55,10 @@ fn build_wrapper(opencv: pkg_config::Library) {
  println!("cargo:rerun-if-changed=gen_rust.py");
  let out_dir = PathBuf::from(std::env::var("OUT_DIR").unwrap());
  + // detect building for docs.rs
  + if out_dir.starts_with("/home/cratesfyi/cratesfyi/debug/build/") {
  + return;
  + }
  let out_dir_as_str = out_dir.to_str().unwrap();
  let hub_dir = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap()).join("src");
  let module_dir = hub_dir.join("hub");
  