Auto merge of #109577 - jonhoo:long-tar-names, r=Mark-Simulacrum

[rust-installer] Allow long link names in tar files

Without this, users trying to run `x.py dist` under a sufficiently long path run into problems when we build the resulting tarballs due to length limits in the original tar spec. The error looks like:

        Finished release [optimized + debuginfo] target(s) in 0.34s
    Copying stage0 std from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-musl)
    Building stage0 tool rust-installer (x86_64-unknown-linux-gnu)
        Finished release [optimized] target(s) in 0.35s
    Dist rust-std-1.67.1-x86_64-unknown-linux-musl
    Error: failed to generate installer

    Caused by:
        0: failed to tar file '/home/AAAAAAAAAAAAAA/BBBBBB/CCCC/DDD/EEEEE/FFFFFFFFFFFF/GGGGGGGGGGGGGGGG/HHHHHHHHHH/IIIIIIIIIIIIIII/JJJJJ/KKKKKKK/src/build/tmp/tarball/rust-std/x86_64-unknown-linux-musl/rust-std-1.67.1-x86_64-unknown-linux-musl/rust-std-x86_64-unknown-linux-musl/lib/rustlib/x86_64-unknown-linux-musl/lib/self-contained/libc.a'
        1: provided value is too long when setting link name for
    Build completed unsuccessfully in 0:00:03

The fix is to make use of the widely-supported GNU tar extensions which lift this restriction. Switching to [`tar::Builder::append_link`] takes care of that for us. See also alexcrichton/tar-rs#273.

[`tar::Builder::append_link`]: https://docs.rs/tar/0.4.38/tar/struct.Builder.html#method.append_link

Author: bors