Implement VRANDMEMBER

`VRANDMEMBER` has the exact same semantics of `SRANDMEMBER` so make
`SRANDMEMBER` a keyword based command and use it for `VRANDMEMBER`.

See #2543

redis.stub.php

@@ -4281,6 +4281,14 @@ class Redis {
      */
     public function vemb(string $key, mixed $member, bool $raw = false): Redis|array|false;
 
+    /**
+     * Get one or more random members from a vector set
+     *
+     * @param string $key   The vector set to query.
+     * @param int $count    The number of random members to return.
+     */
+    public function vrandmember(string $key, int $count = 0): Redis|array|string|false;
+
     /**
      * Truncate a STREAM key in various ways.
      *