Support the NOVALUES option of HSCAN (#2711)

* Support the NOVALUES option of HSCAN

Issue #2705

The NOVALUES option instructs HSCAN to only return keys, without their
values. This is materialized as a new command, `hScanNoValues`, given
that the return type is different from the usual return type of `hScan`.
Also a new iterator is provided, `hScanNoValuesIterator`, for the same
reason.

* skip hscan novalues test if redis < 7.4

* Also don't test hscan no values iterator < 7.4

---------

Co-authored-by: Shaya Potter <spotter@gmail.com>

packages/client/lib/commands/HSCAN_NOVALUES.ts

@@ -0,0 +1,27 @@
+import { RedisCommandArgument, RedisCommandArguments } from '.';
+import { ScanOptions } from './generic-transformers';
+import { HScanRawReply, transformArguments as transformHScanArguments } from './HSCAN';
+
+export { FIRST_KEY_INDEX, IS_READ_ONLY } from './HSCAN';
+
+export function transformArguments(
+    key: RedisCommandArgument,
+    cursor: number,
+    options?: ScanOptions
+): RedisCommandArguments {
+    const args = transformHScanArguments(key, cursor, options);
+    args.push('NOVALUES');
+    return args;
+}
+
+interface HScanNoValuesReply {
+    cursor: number;
+    keys: Array<RedisCommandArgument>;
+}
+
+export function transformReply([cursor, rawData]: HScanRawReply): HScanNoValuesReply {
+    return {
+        cursor: Number(cursor),
+        keys: [...rawData]
+    };
+}