fix(test): Stub MySQL connect method instead of calling the original

The MySQL driver now connects directly to the driver, instead on the first query. This
caused some trouble with the ssh tunnel test, this functionality was stubbed.

Fixes #348

test/driver/index_test.js

@@ -24,9 +24,8 @@ var indexConnectCallback = function(self, tunnelStub, driverSpy) {
       self.callback(err, db, tunnelStub, driverSpy);
       return;
     }
-    db.close(function() {
-      self.callback(err, db, tunnelStub, driverSpy);
-    });
+
+    self.callback(err, db, tunnelStub, driverSpy);
   };
 };
 
@@ -38,7 +37,7 @@ vows.describe('index').addBatch({
       var driver = require('db-migrate-mysql');
 
       // Set up stubs/spies to verify correct flow
-      var driverSpy = sinon.spy(driver, 'connect');
+      var driverSpy = sinon.stub(driver, 'connect').yields(null, {});
       var tunnelStub = sinon.stub().callsArg(1);
 
       var index = proxyquire('../../lib/driver/index', {
@@ -87,7 +86,7 @@ vows.describe('index').addBatch({
 
       // Set up stubs/spies to verify correct flow
       var tunnelStub = sinon.stub().callsArgWith(1, new Error('error'));
-      var driverSpy = sinon.spy(driver, 'connect');
+      var driverSpy = sinon.stub(driver, 'connect').yields(null, {});
 
       var index = proxyquire('../../lib/driver/index', {
         'tunnel-ssh': tunnelStub,