Mention PR #6288 in CHANGELOG.md.

CHANGELOG.md

@@ -62,6 +62,9 @@
 - The `cache.evict` method can optionally take an arguments object as its third parameter (following the entity ID and field name), to delete only those field values with specific arguments. <br/>
   [@danReynolds](https://github.com/danReynolds) in [#6141](https://github.com/apollographql/apollo-client/pull/6141)
 
+- Cache methods that would normally trigger a broadcast, like `cache.evict`, `cache.writeQuery`, and `cache.writeFragment`, can now be called with a named options object, which supports a `broadcast: boolean` property that can be used to silence the broadcast, for situations where you want to update the cache multiple times without triggering a broadcast each time. <br/>
+  [@benjamn](https://github.com/benjamn) in [#6288](https://github.com/apollographql/apollo-client/pull/6288)
+
 - The contents of the `@apollo/react-hooks` package have been merged into `@apollo/client`, enabling the following all-in-one `import`:
   ```ts
   import { ApolloClient, ApolloProvider, useQuery } from '@apollo/client';