Add a PR template

.github/pull_request_template.md

@@ -0,0 +1,13 @@
+<!--
+* Keep your PR:s small and focused.
+* The PR title is what ends up in the changelog, so make it descriptive!
+* If applicable, add a screenshot or gif.
+* Do NOT open PR:s from your `main` branch, as that makes it hard for maintainers to test and add commits to your PR.
+* Remember to run `cargo fmt` and `cargo clippy`.
+* Open the PR as a draft until you have self-reviewed it and it passes CI.
+* When you have addressed a PR comment, mark it as resolved.
+
+Please be patient!
+-->
+
+* Closes #ISSUE_NUMBER