Update Cosmos release date for next version (Azure#17858)

Author: ealsur

sdk/data/azcosmos/CHANGELOG.md

@@ -1,6 +1,6 @@
 # Release History
 
-## 0.3.0 (Unreleased)
+## 0.3.0 (2022-05-10)
 
 ### Features Added
 * Added single partition query support.
@@ -9,10 +9,6 @@
 ### Breaking Changes
 * This module now requires Go 1.18
 
-### Bugs Fixed
-
-### Other Changes
-
 ## 0.2.0 (2022-01-13)
 
 ### Features Added