Fix inconsistencies in contract/test hierachy (#2814)

* Fix inconsistencies in contract/test hierachy

* changelog entry

CHANGELOG.md

@@ -5,6 +5,7 @@
  * `ERC2771Context`: use private variable from storage to store the forwarder address. Fixes issues where `_msgSender()` was not callable from constructors. ([#2754](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2754))
  * `EnumerableSet`: add `values()` functions that returns an array containing all values in a single call. ([#2768](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2768))
  * `Governor`: added a modular system of `Governor` contracts based on `GovernorAlpha` and `GovernorBravo`. ([#2672](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2672))
+ * Fix hierarchy inconsistencies between `contracts` and `test` introduced during the 4.0 repo refactor. ([#2814](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2814))
 
 ## 4.2.0 (2021-06-30)