Generalize patching to support vendoring

[vyasr]

This PR makes a number of significant changes to the patching infrastructure:

1. This PR reorganizes the patching logic to be based on a more principled approach. Rather than maintaining lists of patch functions that are each responsible for filtering modules to apply themselves to, patches are organized in the patches directory in a tree structure matching dask itself. Patches are found and run by importing the same relative paths within the patches directory corresponding to a particular dask or distributed module.
2. It adds proper support for patching submodules. Previously the loader was being disabled whenever a real dask module was being imported, but this is problematic because if some dask modules import others they will pre-populate sys.modules with the real modules and therefore the loader will never be used for loading a patched version of the submodule.
3. Patches are no longer just functions applied to modules, they are arbitrary functions executed when a module is imported. As a result, a wider range of modifications is possible than was previously allowed. In particular:
4. The more general functions allow the entire module import to be hijacked and redirected to other modules.
5. The new framework is used to vendor a patched version of the accessor.py module in dask, which resolves the issues observed in Fix dask.dataframe import error for Python 3.11.9 dask/dask#11035.

[rjzamora]

Wow - This is impressive. I'm a bit scared of the complexity here, but I doubt there is a much simpler way to achieve what we need.

[rjzamora]

I wonder if the following sequence of events make sense?

1. Port/merge Check test exit codes. #37 to 24.06
2. Test/review this PR a bit further (simple things are working for me locally)
3. (optional?) Remove the __rdd_patch_accessor.py file from this PR, since it only applies to 24.04 (Edit: Lawrences suggestion accounts for this)
4. Backport all patching/testing to 24.04
5. (optional?) Add __rdd_patch_accessor.py file to 24.04

[wence-]

I like this and have only one minor suggestion to restrict the scope of patching the vendored file.

[bdice]

The changes look good to me, now that the patch is applied only to the affected Python/Dask versions. (I have not verified that this passes locally.)

[rjzamora]

This is heroic work @vyasr - Thanks for saving the day!

[rjzamora]

\merge

[raydouglass]

This PR was reverted via force push so that it can be merged via the bot instead (in #39).