fix mixpanel provider implementation
fix mixpanel provider implementation

twobitlabs/AnalyticsKit,busybusy/AnalyticsKit,twobitlabs/AnalyticsKit,twobitlabs/AnalyticsKit,busybusy/AnalyticsKit,brightredchilli/AnalyticsKit,brightredchilli/AnalyticsKit,busybusy/AnalyticsKit,busybusy/AnalyticsKit