docs: update changelog

Author: Ahmad Nurjalal

CHANGELOG.md

@@ -1,3 +1,62 @@
+<a name="v0.4.0"></a>
+## [v0.4.0] - 2022-02-15
+
+### Chore
+- version bump
+- fix broken gradle files
+- publish to nexus on release stage
+- add missing timestamp check
+- add test stage
+- **api:** regenerate services
+- **samples:** regenerate cli
+- **spec:** update spec files
+- **spec:** add timestamp and lobby wsm spec
+
+### Ci
+- build samples
+- **coverity:** initial commit
+
+### Docs
+- update changelog
+- **samples:** fix readme cli
+
+### Feat
+- websocket core class
+- add junit
+- **api:** add websocket message models
+- **api:** add function to get collection format and array query string
+- **core:** add logic to handle array within query string
+- **core:** add helper functions for websocket implementation
+- **sample:** add java sdk cli
+- **samples:** update dependency
+- **samples:** java-sdk-poc - get dependency from nexus
+- **samples:** java sdk websocket poc
+- **test:** add unit tests against mock server
+
+### Fix
+- upload file handling
+- **api:** delete unnecessary variable
+- **api:** incorrect form data params value assignment
+- **core:** set encoding to utf8 instead of system default
+- **core:** handle tsv, ssv, pipes collection format
+- **core:** invalid get form data params checking
+- **core:** invalid request method and body
+- **core:** set default content type if not declared
+- **core:** websocket singleton object
+- **core:** thread safe singleton declaration
+- **okhttpclient:** use shared okhttpclient and don't swallow jsonprocessingexception
+- **operation:** revise create url a little bit
+- **operation:** make convertInputStreamToString protected
+- **sample:** invalid exit code on cli apps
+- **sample:** change input stream to file for cli input
+- **samples:** set null on unfilled parameter in form data
+- **samples:** change websocket class implementation
+- **wrappers:** close httpresponse payload stream after parsing
+
+### Test
+- add test for all collection format type
+- add test for query string params
+
 <a name="v0.3.0"></a>
 ## [v0.3.0] - 2022-02-03
 
@@ -67,17 +126,18 @@
 - **api:** regenerate services
 - update APIs:
   - cloudsave
-      - add, update endpoints
+    - add, update endpoints
   - group
-      - update endpoints
+    - update endpoints
   - iam
-      - add, update endpoints
+    - add, update endpoints
   - legal
-      - add, update endpoints
+    - add, update endpoints
   - lobby
-      - update endpoints
+    - update endpoints
   - platform
-      - add, update endpoints
+    - add, update endpoints
 
+[v0.4.0]: https://github.com/AccelByte/accelbyte-java-sdk/compare/v0.3.0...v0.4.0
 [v0.3.0]: https://github.com/AccelByte/accelbyte-java-sdk/compare/v0.2.0...v0.3.0
 [v0.2.0]: https://github.com/AccelByte/accelbyte-java-sdk/compare/v0.1.0...v0.2.0