Remove y.rs

It has been deprecated for over a year now.

rustfmt.toml

@@ -1,5 +1,4 @@
 ignore = [
-    "y.rs",
     "example/gen_block_iterate.rs", # uses edition 2024
 ]
 

y.rs

@@ -1,6 +0,0 @@
-#!/usr/bin/env bash
-#![deny(unsafe_code)] /*This line is ignored by bash
-# This block is ignored by rustc
-echo "Warning: y.rs is a deprecated alias for y.sh" 1>&2
-exec ./y.sh "$@"
-*/