Create pull_request_template.md

.github/pull_request_template.md

@@ -0,0 +1,20 @@
+## Before requesting a review
+
+- [ ] if the PR is WIP - use draft mode
+- [ ] made a self-review
+- [ ] added inline comments where things may be not obvious (the "why", not "what")
+- [ ] what kind of review is needed?
+  - [ ] conceptual
+  - [ ] detailed
+  - [ ] with testing
+
+##  Test cases
+
+- [ ] step by step interaction description and what is expected to happen
+
+## Before merging
+
+- [ ] tested locally and on preview environment
+- [ ] updated [test cases](https://github.com/webstudio-is/webstudio-designer/blob/main/apps/designer/docs/test-cases.md) document 
+- [ ] added tests
+- [ ] if any new env variables are added, added them to `.env.example` and the `designer/env-check.js` if mandatory