Update release notes for v0.8.0

Removed testing section from release notes for v0.8.0.

Author: krinart

docs/release_notes/v0.8.0.md

@@ -35,10 +35,6 @@ System.out.println(response.getData());
 String sql = client.nsqlGenerateSql(new NsqlRequest("how many trips were over 10 miles?"));
 ```
 
-## Testing
-
-- New unit test suites (`SearchTest`, `NsqlTest`) covering request/response shape, validation, and error handling, all against local mock servers with no live runtime required.
-
 ## Compatibility
 
 - Public API unchanged: both features are new methods; nothing existing was renamed, removed, or retyped.