Cleanup after v1.2.0 release

Author: xiaozhu36

CHANGELOG.md

@@ -1,12 +1,7 @@
-## 1.2.0 (Unreleased)
+## 1.3.0 (Unreleased)
 ## 1.2.0 (January 16, 2020)
 
 IMPROVEMENTS:
 
 - Add variables type and CHANGELOG.md [GH-4](https://github.com/terraform-alicloud-modules/terraform-alicloud-mongodb/pull/4)
-
-## 1.0.0 (January 16, 2020)
-
-IMPROVEMENTS:
-
-- imporve(mongodb): update the module to the format of the new version [GH-3](https://github.com/terraform-alicloud-modules/terraform-alicloud-mongodb/pull/3)
+- imporve(mongodb): update the module to the format of the new version [GH-3](https://github.com/terraform-alicloud-modules/terraform-alicloud-mongodb/pull/3)