Update changelog for SR for 2.8.0 (#1378)

Author: rayokota

CHANGELOG.md

@@ -10,6 +10,23 @@ for a complete list of changes, enhancements, fixes and upgrade considerations.
 
 There was no v2.7.0 release.
 
+### Enhancements
+
+* Add retry logic to RestService for Schema Registry (#1337)
+* Add ability to override disable flag and actions on a rule (#1356)
+* Add AWS AssumeRole support to AWS KMS (#1359)
+* Add support for comma-separated URLs (#1364)
+ 
+### Fixes
+
+* Add deleted query param when looking up schema under subject (#1340)
+* For Protobuf, copy the result into the target if necessary (#1347)
+* Don't register maps as native types in CEL rules (#1348)
+* Lookup local secret from env if needed (#1349)
+* Ensure different key ids use different client instances (#1352)
+* Fix handling of nested maps for Avro and JSON Schema (#1355)
+* Ensure algorithm query param is passed for CSFLE (#1373)
+
 
 ## v2.6.1