Prepare changelog for 1.53.0 (#7533)

Author: breedx-splk

CHANGELOG.md

@@ -2,6 +2,17 @@
 
 ## Unreleased
 
+### SDK
+
+* File based config will log the wrong file format, when applicable.
+  ([#7498](https://github.com/open-telemetry/opentelemetry-java/pull/7498))
+
+#### Exporters
+
+* Change `okhttp` dependency to `okhttp-jvm`, which fixes missing class failures in
+  transitive dependencies.
+  ([#7517](https://github.com/open-telemetry/opentelemetry-java/pull/7517))
+
 ## Version 1.52.0 (2025-07-11)
 
 ### API