Removed TempFile and TempDirectory from FileSystemWatcher Tests (#68444)

Removed TempFile and TempDirectory from FileSystemWatcher Tests (#68444)

* Removed TempFile and TempDirectory from FileSystemWatcher Tests

* Added missing CreateDirectory

* Removed redundant variables

* removed redundant variable

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* removed redundant variable

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* removed redundant variable

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* Fixed directory name

* Reverted changes

* Simplified

* made local tests

* substituted methods

* fix

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* Update src/libraries/Common/tests/TestUtilities/System/IO/FileCleanupTestBase.cs

spacing

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* spacing

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* remove redundant file creation

Co-authored-by: Dan Moseley <danmose@microsoft.com>
* fixes

* fix

* applied suggestions, removed redundant variables

* spacing

* Fix casing bug

Co-authored-by: Dan Moseley <danmose@microsoft.com>