Bump cherrypy from 18.8.0 to 18.9.0 (#2266)

* Bump cherrypy from 18.8.0 to 18.9.0

Bumps [cherrypy](https://github.com/cherrypy/cherrypy) from 18.8.0 to 18.9.0.
- [Changelog](https://github.com/cherrypy/cherrypy/blob/main/CHANGES.rst)
- [Commits](https://github.com/cherrypy/cherrypy/compare/v18.8.0...v18.9.0)

---
updated-dependencies:
- dependency-name: cherrypy
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* Update cherrypy==18.9.0

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: JonnyWong16 <9099342+JonnyWong16@users.noreply.github.com>

[skip ci]

lib/isapi/samples/README.txt

@@ -0,0 +1,20 @@
+In this directory you will find examples of ISAPI filters and extensions.
+
+The filter loading mechanism works like this:
+* IIS loads the special Python "loader" DLL.  This DLL will generally have a 
+  leading underscore as part of its name.
+* This loader DLL looks for a Python module, by removing the first letter of
+  the DLL base name.
+  
+This means that an ISAPI extension module consists of 2 key files - the loader
+DLL (eg, "_MyIISModule.dll", and a Python module (which for this example
+would be "MyIISModule.py")
+
+When you install an ISAPI extension, the installation code checks to see if
+there is a loader DLL for your implementation file - if one does not exist, 
+or the standard loader is different, it is copied and renamed accordingly.
+
+We use this mechanism to provide the maximum separation between different
+Python extensions installed on the same server - otherwise filter order and
+other tricky IIS semantics would need to be replicated.  Also, each filter
+gets its own thread-pool, etc.