Add missing argument in depthCache method

Add missing argument to avoid the following error: "Too few arguments to function Binance\API::depth()" when using depth cache via WebSockets

Author: ComeLC

php-binance-api.php

@@ -1764,7 +1764,7 @@ public function depthCache($symbols, callable $callback)
                 echo "depthCache({$symbol})) Could not connect: {$e->getMessage()}" . PHP_EOL;
                 $loop->stop();
             });
-            $this->depth($symbol);
+            $this->depth($symbol, 100);
             foreach ($this->depthQueue[$symbol] as $data) {
                 //TODO:: WTF ??? where is json and what should be in it ??
                 $this->depthHandler($json);