git-branchless: fix build (broken by rust 1.89) (#437517)

diff --git a/src/lock.rs b/src/lock.rs

--- a/src/lock.rs

+++ b/src/lock.rs

@@ -132,10 +132,10 @@ impl ScopedDirLock {

         // Lock

         match (opts.exclusive, opts.non_blocking) {

-            (true, false) => file.lock_exclusive(),

-            (true, true) => file.try_lock_exclusive(),

-            (false, false) => file.lock_shared(),

-            (false, true) => file.try_lock_shared(),

+            (true, false) => fs2::FileExt::lock_exclusive(&file),

+            (true, true) => fs2::FileExt::try_lock_exclusive(&file),

+            (false, false) => fs2::FileExt::lock_shared(&file),

+            (false, true) => fs2::FileExt::try_lock_shared(&file),

         }

         .context(&path, || {

             format!(

    hash = "sha256-8uv+sZRr06K42hmxgjrKk6FDEngUhN/9epixRYKwE3U=";

  };

  # Patch the vendored esl01-indexedlog crate.

  # This is necessary to fix the build for rust 1.89. See:

  # - https://github.com/NixOS/nixpkgs/issues/437051

  # - https://github.com/arxanas/git-branchless/issues/1585

  # - https://github.com/facebook/sapling/issues/1119

  # The patch is derived from:

  # - https://github.com/facebook/sapling/commit/9e27acb84605079bf4e305afb637a4d6801831ac

  postPatch = ''

    (

      cd ../git-branchless-*-vendor/esl01-indexedlog-*/

      patch -p1 < ${./fix-esl01-indexedlog-for-rust-1_89.patch}

    )

  '';

  cargoHash = "sha256-i7KpTd4fX3PrhDjj3R9u98rdI0uHkpQCxSmEF+Gu7yk=";

  nativeBuildInputs = [ pkg-config ];