Remove PHP tests and create tests for cases that are useful to keep (#1505)

* Remove PHP tests and create tests for cases that are useful to keep

Resolves #1480

* Update changelog

Author: facelessuser

docs/changelog.md

@@ -13,6 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 * DRY fix in `abbr` extension by introducing method `create_element` (#1483).
+* Clean up test directory some removing some redundant tests and port
+  non-redundant cases to the newer test framework.
 
 ### Fixed