[roll] Roll fuchsia Revert "[build] Add vpython3 to tool_paths.json"

This reverts commit 5986ba07321bca12b320d5852b4ae1f0e5199458.

Reason for revert: We actually don't need this, I was able to get the sdk recipe to work with Python 3 without using vpython (see fxrev.dev/601321).

Original change's description:
> [build] Add vpython3 to tool_paths.json
>
> So the sdk recipe can use vpython for invoking SDK scripts. I was hoping
> to be able to stop using vpython entirely, but that causes some
> breakages on Mac, so instead I'm going to just make sure that the recipe
> uses the versions of vpython3 and python3 that are included in the
> checkout.
>
> Original-Bug: 77963
> Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/601202

Original-Bug: 77963
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/602926
Original-Revision: 241c32003ec2e55e2567def25aaccfbecb10275a
GitOrigin-RevId: 7aed56bdc1f27003b1088d74b814635175bbfa4a
Change-Id: Id8568b7e0721f2e31e31b77898660b4750478425
diff --git a/stem b/stem
index 3c1aa49..80e2cc7 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="2fb8e6190ca565c454b174cd4ca27fa00cf64a57"/>
+             revision="241c32003ec2e55e2567def25aaccfbecb10275a"/>
   </projects>
   <hooks>
     <hook name="install-environment"