otlp: Add changelog entry for DeltaTemporalitySelector

Author: svix-jplatte

opentelemetry-otlp/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## vNext
 
+### Added
+
+- Added `DeltaTemporalitySelector` ([#1568])
+
 ### Fixed
 - Fix `tonic()` to the use correct port. [#1556](https://github.com/open-telemetry/opentelemetry-rust/pull/1556)
 
@@ -12,6 +16,8 @@
 - **Breaking** Remove support for surf HTTP client [#1537](https://github.com/open-telemetry/opentelemetry-rust/pull/1537)
 - Remove support for grpcio transport (#1534)
 
+[#1568]: https://github.com/open-telemetry/opentelemetry-rust/pull/1568
+
 ## v0.14.0
 
 ### Added