remove debug keys in favor of entries

tests/gc/main.rs

@@ -1,3 +1,14 @@
+macro_rules! assert_keys {
+    ($db:expr, $($query:expr => ($($key:expr),*),)*) => {
+        $(
+            let entries = $db.query($query).entries::<Vec<_>>();
+            let mut keys = entries.into_iter().map(|e| e.key).collect::<Vec<_>>();
+            keys.sort();
+            assert_eq!(keys, vec![$($key),*], "query {:?} had wrong keys", $query);
+        )*
+    };
+}
+
 mod db;
 mod derived_tests;
 mod discard_values;