updates PR template

Author: latin-panda

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,14 +1,12 @@
+> [!WARNING]
+> Branch off and target `next`, not `master`. The `master` is stable and used in production (exception: documentation/infrastructure-only changes).
+
 Closes #
 
 #### What has been done to verify that this works as intended?
 
 #### Why is this the best possible solution? Were any other approaches considered?
 
-#### How does this change affect users? Describe intentional changes to behavior and behavior that could have accidentally been affected by code changes. In other words, what are the regression risks?
+#### How does this change impact users? Describe intentional behavior changes from code updates. What are the regression risks?
 
 #### Does this change require updates to documentation? If so, please file an issue [here](https://github.com/getodk/docs/issues/new) and include the link below.
-
-#### Before submitting this PR, please make sure you have:
-
-- [ ] branched off and targeted the `next` branch OR only changed documentation/infrastructure (`master` is stable and used in production)
-- [ ] verified that any code or assets from external sources are properly credited in comments or that everything is internally sourced