Update pull_request_template.md to improve full ETL instructions (#3446)

* Update pull_request_template.md to improve full ETL instructions

The full ETL often can't be run locally. These edits 1) move the full ETL to be the last item in the checklist, reflecting the fact that it should be run after all other items are checked off and 2) highlights the particular GHA that can be used to run the full ETL on batch if it cannot be run on one's local device.

* Clarify validation tests

* Update distinction between minor and major changes

.github/pull_request_template.md

@@ -17,10 +17,10 @@ How did you make sure this worked? How can a reviewer verify this?
 
 ```[tasklist]
 # To-do list
-- [ ] Ensure docs build, unit & integration tests, and test coverage pass locally with `make pytest-coverage` (otherwise the merge queue may reject your PR)
-- [ ] For significant ETL changes, ensure the full ETL runs locally
-- [ ] For major data coverage & analysis changes, [run data validation tests](https://catalystcoop-pudl.readthedocs.io/en/latest/dev/testing.html#data-validation)
-- [ ] If updating analyses or data processing functions: make sure to update or write data validation tests
+- [ ] If updating analyses or data processing functions: make sure to update or write data validation tests (e.g.,  `test_minmax_rows()`)
 - [ ] Update the [release notes](../docs/release_notes.rst): reference the PR and related issues.
+- [ ] Ensure docs build, unit & integration tests, and test coverage pass locally with `make pytest-coverage` (otherwise the merge queue may reject your PR)
 - [ ] Review the PR yourself and call out any questions or issues you have
+- [ ] For minor ETL changes or data additions, once `make pytest-coverage` passes, make sure you have a fresh full PUDL DB downloaded locally, materialize new/changed assets and all their downstream assets and [run relevant data validation tests] (https://catalystcoop-pudl.readthedocs.io/en/latest/dev/testing.html#data-validation) using `pytest` and `--live-dbs`.
+- [ ] For significant ETL, data coverage or analysis changes, once `make pytest-coverage` passes, ensure the full ETL runs locally and [run all data validation tests] (https://catalystcoop-pudl.readthedocs.io/en/latest/dev/testing.html#data-validation) using `make pytest-validate` (together, expect a ~10 hour run). If you can't run this locally , run the `build-deploy-pudl` GitHub Action (or ask someone else with permissions to do so on your behalf). Then, check the `#pudl-deployments` Slack channel or [builds.catalyst.coop] (builds.catalyst.coop) to find the logs for the validation tests and ensure all tests passed.
 ```