Merge 2.7 into 3.0

Author: soyuka

CHANGELOG.md

@@ -155,6 +155,13 @@ Breaking changes:
 * Metadata: `Patch` is added to the automatic CRUD
 * Symfony: generated route names and operation names changed, route naming can be changed directly within metadata
 
+## v2.7.9
+
+### Bug fixes
+
+* [1983089d9](https://github.com/api-platform/core/commit/1983089d9c2de4bb9fc36c60929aff538af89b8e) fix(metadata): reader should be nullable (#5378)
+* [80aeb3158](https://github.com/api-platform/core/commit/80aeb3158311ff4ce9ad28b7f813dedee7744828) fix(symfony): autoconfigure elasticsearch extension (#5379)
+
 ## v2.7.8
 
 ### Bug fixes