Make WASI's hard_link behavior match other platforms.

Following rust-lang#78026, `std::fs::hard_link` on most platforms does not follow
symlinks. Change the WASI implementation to also not follow symlinks.

library/std/src/sys/wasi/fs.rs

@@ -557,8 +557,9 @@ pub fn symlink(original: &Path, link: &Path) -> io::Result<()> {
 pub fn link(original: &Path, link: &Path) -> io::Result<()> {
     let (original, original_file) = open_parent(original)?;
     let (link, link_file) = open_parent(link)?;
+    // Pass 0 as the flags argument, meaning don't follow symlinks.
     original.link(
-        wasi::LOOKUPFLAGS_SYMLINK_FOLLOW,
+        0,
         osstr2str(original_file.as_ref())?,
         &link,
         osstr2str(link_file.as_ref())?,