Merge pull request #1340 from atsign-foundation/publish_3.0.76

chore: Update CHANGELOG.md to publish v3.0.76

Author: sitaram-kalluri

packages/at_client/CHANGELOG.md

@@ -1,5 +1,8 @@
 ## 3.0.76
 - feat: Introduce mechanism to identify and delete expired keys
+- feat: Introduce enrollment service to support enrollment operations:
+  - Submit enrollment request(s)
+  - Approve, Deny and Revoke enrollment request(s)
 ## 3.0.75
 - feat: Introduce feature to fetch enrollment requests from the server
 ## 3.0.74