Rollup merge of #123687 - bjorn3:ar_archive_writer_0_2_0, r=oli-obk

Update ar_archive_writer to 0.2.0

This adds a whole bunch of tests checking for any difference with llvm's archive writer. It also fixes two mistakes in the porting from C++ to Rust. The first one causes a divergence for Mach-O archives which may or may not be harmless. The second will definitively cause issues, but only applies to thin archives, which rustc currently doesn't create.

Author: GuillaumeGomez