Update CHANGELOG

Author: zihejia

CHANGELOG.md

@@ -1,5 +1,18 @@
 #
 
+## [v1.4.0](https://github.com/mixpanel/mixpanel-flutter/tree/v1.4.0) (2021-12-02)
+
+### Enhancements
+
+- Add web support [\#35](https://github.com/mixpanel/mixpanel-flutter/pull/35)
+
+**Closed issues:**
+
+- App crash on init [\#32](https://github.com/mixpanel/mixpanel-flutter/issues/32)
+- Event tracking order changes when more than one event is passed at the exact same event. [\#23](https://github.com/mixpanel/mixpanel-flutter/issues/23)
+
+#
+
 ## [v1.3.1](https://github.com/mixpanel/mixpanel-flutter/tree/v1.3.1) (2021-09-25)
 
 ### Enhancements
@@ -70,3 +83,5 @@
 
 
 
+
+