docs(CHANGELOG): Revert relase 2.1.0 to avoid breaking changes.
docs(CHANGELOG): Revert relase 2.1.0 to avoid breaking changes.

Revert relase [2.1.0](https://github.com/estools/espurify/releases/tag/v2.1.0) since it affects to AST matching logic and breaks [some usecases](https://github.com/unassert-js/unassert/issues/18).

estools/espurify