Replace TestCase method aliases removed in Python 3.12

Fixes: #568

Author: hrnciar

Diff for: CHANGELOG.md

@@ -21,6 +21,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   ([#535](https://github.com/PyFilesystem/pyfilesystem2/issues/535)).
 - Fixed a bug where files could be truncated or deleted when moved / copied onto itself.
   Closes [#546](https://github.com/PyFilesystem/pyfilesystem2/issues/546)
+- TestCase method aliases removed in Python 3.12 were replaced and now work with all Python versions.
+  Closes [#568](https://github.com/PyFilesystem/pyfilesystem2/issues/568)
 
 ## [2.4.16] - 2022-05-02
 

Diff for: CONTRIBUTORS.md

@@ -41,6 +41,7 @@ Many thanks to the following developers for contributing to this project:
 - [@sqwishy](https://github.com/sqwishy)
 - [Sven Schliesing](https://github.com/muffl0n)
 - [Thomas Feldmann](https://github.com/tfeldmann)
+- [Tomáš Hrnčiar](https://github.com/hrnciar)
 - [Tim Gates](https://github.com/timgates42/)
 - [@tkossak](https://github.com/tkossak)
 - [Todd Levi](https://github.com/televi)

Diff for: fs/test.py

@@ -1082,7 +1082,7 @@ def test_remove(self):
         self.fs.makedirs("foo/bar/baz/")
 
         error_msg = "resource 'foo/bar/egg/test.txt' not found"
-        assertRaisesRegex = getattr(self, "assertRaisesRegex", self.assertRaisesRegexp)
+        assertRaisesRegex = getattr(self, "assertRaisesRegex", self.assertRaisesRegex)
         with assertRaisesRegex(errors.ResourceNotFound, error_msg):
             self.fs.remove("foo/bar/egg/test.txt")