Mention PR #6837 in CHANGELOG.md.

CHANGELOG.md

@@ -33,6 +33,9 @@
 - Allow `cache.modify` functions to return `details.INVALIDATE` (similar to `details.DELETE`) to invalidate the current field, causing affected queries to rerun, even if the field's value is unchanged. <br/>
   [@benjamn](https://github.com/benjamn) in [#6991](https://github.com/apollographql/apollo-client/pull/6991)
 
+- Move `apollo-link-persisted-queries` implementation to `@apollo/client/link/persisted-queries`. Try running our [automated imports transform](https://github.com/apollographql/apollo-client/tree/main/codemods/ac2-to-ac3) to handle this conversion, if you're using `apollo-link-persisted-queries`. <br/>
+  [@hwillson](https://github.com/hwillson) in [#6837](https://github.com/apollographql/apollo-client/pull/6837)
+
 ## Apollo Client 3.1.4
 
 ## Bug Fixes