chore(wolfcrypt-rs): remove broken builder symlink

wolfcrypt-rs/builder was a symlink to ../builder which does not exist
in this repository. Nothing in the build script or source references
it. Cargo fails to package the crate because it tries to archive the
dangling symlink target.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: MarkAtwood