Remove saucelab creds from circle.yml, clean up logic syntax

Author: ladannasserian

circle.yml

@@ -4,8 +4,6 @@ machine:
   environment:
     NPM_CONFIG_PROGRESS: false
     NPM_CONFIG_SPIN: false
-    SAUCE_ACCESS_KEY: 80dcffc2-c9a2-45e2-9fb7-87b29a6cd986
-    SAUCE_USERNAME: segment-oss
     TEST_REPORTS_DIR: $CIRCLE_TEST_REPORTS
 
 dependencies:

lib/index.js

@@ -238,9 +238,7 @@ Mixpanel.prototype.track = function(track) {
   var superProps = pick(this.options.superProperties, props);
   var sourceName = this.options.sourceName;
 
-  if (sourceName) {
-    props.segment_source_name = sourceName;
-  }
+  if (sourceName) props.segment_source_name = sourceName;
 
   // delete mixpanel's reserved properties, so they don't conflict
   delete props.distinct_id;