fix(db-util): encode epoch key

Author: egasimus

util/src/main.rs

@@ -18,8 +18,8 @@ fn main () -> Result<(), Box<dyn Error>> {
     println!("{height:?}");
 
     let block_cf = db.cf_handle("block").expect("no cf: block");
-    let key = format!("{height}/epoch");
-    let err = format!("no epoch in block cf, key: {key}");
+    let key = [h[0], h[1], h[2], h[3], h[4], h[5], h[6], h[7], b'/', b'e', b'p', b'o', b'c', b'h'];
+    let err = format!("no epoch in block cf, key: {key:x}");
     let e = db.get_cf(block_cf, &key)?.expect(&err);
     let epoch = u64::from_le_bytes([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7]]);
     println!("{epoch:?}");