gemini: fixing lint errors

Author: bmancini55

__tests__/exchanges/gemini-client.spec.js

@@ -68,7 +68,7 @@ testClient({
   },
 
   l2update: {
-    done: function(spec, result, update, market) {
+    done: function(spec, result, update) {
       const hasAsks = update.asks && update.asks.length > 0;
       const hasBids = update.bids && update.bids.length > 0;
       return hasAsks || hasBids;

src/exchanges/gemini-client.js

@@ -259,7 +259,7 @@ class GeminiClient extends EventEmitter {
       // ex: '{"type":"heartbeat","socket_sequence":272}'
       /*
         A few notes on heartbeats and sequenceIds taken from the Gemini docs:
-        - Ongoing order events are interspersed with heartbeats every five seconds 
+        - Ongoing order events are interspersed with heartbeats every five seconds
         - So you can easily ensure that you are receiving all of your WebSocket messages in the expected order without any gaps, events and heartbeats contain a special sequence number.
         - Your subscription begins - you receive your first event with socket_sequence set to a value of 0
         - For all further messages, each message - whether a heartbeat or an event - should increase this sequence number by one.