flows: add shortcut to redirect current flow (#3192)

website/docs/flow/examples/snippets.md

@@ -0,0 +1,17 @@
+---
+title: Example policy snippets for flows
+---
+
+### Redirect current flow to another URL
+
+:::info
+Requires authentik 2022.7
+:::
+
+```python
+plan = request.context["flow_plan"]
+plan.redirect("https://foo.bar")
+return False
+```
+
+This policy should be bound to the stage after your redirect should happen. For example, if you have an identification and a password stage, and you want to redirect after identification, bind the policy to the password stage. Make sure the policy binding is set to re-evaluate policies.