This update for gn fixes the following issues:

- Update to version 0.20251217:
  * Fix sha2 on big endian
  * [Windows] Reduce the number of worker threads on many-core machines
  * Add a sha256 hash implementation and use it for string_hash
  * Opt-in to the Windows SegmentHeap
  * Add a `module_name` flag to source_set.
  * Refactor module name to be dynamic.
  * Optimize vector creation in compile_commands_writer.cc.
  * Run 'tools/run_formatter.sh'
  * Implement `string_hash` function.
  * Support weak_libraries
  * Do not add .inputdeps paths to --ninja-outputs-file
  * Make clang modules output -fmodule-file=foo=<pcm>.
  * infra: Revert CIPD autoconf
  * infra: Include autoconf bin directory to PATH
  * infra: Fix autoconf executable path
  * infra: Use CIPD autoconf
  * Allow led access in GN via http://go/ciba
  * Revert "Build non-linkable deps async with Ninja's validaitons"
  * Upgrade linux bots from ubuntu 22.04 to ubuntu 24.04
  * Use unordered_map instead of map in HeaderChecker
  * Add --file_relation to gn refs command
  * Optimize vector initialization and preallocation in desc_builder.cc.
  * Add `reserve` statement when vector size is known beforehand.
  * Refactor container update by preferring the range insert.
  * Handle symlinked directories correctly during gn clean on Windows.
  * Fix relative imports from args.gn.

- Update to version 0.20250918:
  * update reference.md
  * Include -fmodule-file flags in compile_commands.json
  * Refactor C++ module dependency logic into a new utility
  * Gitiles navigation bar
  * Adds a len() function
  * Avoid clashes of include_dir in rust-project.json.
  * Check all targets to find duplicated outputs.
  * infra/config: Remove luci.recipes.use_python3 experiment
  * Handle empty outputs in WriteInputDepsStampOrPhonyAndGetDep
  * build: Propagate module dependencies through group targets
  * Deduplicate item in 'deps', 'sources' and related lists
  * infra: Update comment for macOS version used in CQ/CI
  * [Apple] Allow passing a manifest to the post-processing script
  * Update link to buganizer in README.md
  * [Apple] Fix `gn gen` when using swift and no_stamp_files
  * [Apple] Remove deprecated aliases for `post_processing_$var`
  * Revert "Allow newline in string literal"
  * Use std::ranges::all_of in parse_tree_unittest
  * infra: Correctly use macOS 13 instead of 11
  * Update Xcode and macOS version in bots
  * infra: Add shadow buckets to trigger led job
  * Allow newline in string literal
  * Revert "Update macOS version to 13 used in CQ/CI"
  * Update macOS version to 13 used in CQ/CI
  * Refactor command_format.cc
  * Shorten targets from //path/to/foo:foo to //path/to/foo
  * Modernize and improve parse_tree.cc
  * Auto-format the codebase
  * Remove hardcoded -fmodules-embed-all-files flag
  * Reland "Use JSON escaping for JSON string output"