(BSR) docs(PR): add best practices to template

.github/PULL_REQUEST_TEMPLATE.md

@@ -34,11 +34,23 @@ I have:
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+- Remove type assertions with `as` (type assertions are removed at compile-time, there is no runtime checking associated with a type assertion. There won’t be an exception or `null` generated if the type assertion is wrong). In certain cases `as const` is acceptable (for example when defining readonly arrays/objects). **MUST BE DISCUSSED: using `as` in tests**
+- Remove bypass type checking with `any` (when you want to accept anything because you will be blindly passing it through without interacting with it, you can use `unknown`). **MUST BE DISCUSSED: when defining functions that can take literally anything, it would seem that it is not practical to use `unknown`. Also we should discuss the usage on `any` in tests.**
 - Remove non-null assertion operators (just like other type assertions, this doesn’t change the runtime behavior of your code, so it’s important to only use `!` when you know that the value can’t be `null` or `undefined`).
+- When creating a new component, start by creating it in StoryBook. **MUST BE DISCUSSED: what do we consider a component? Should all components be in StoryBook?**
+- When creating a new logic, start by writing tests (TDD). **MUST BE DISCUSSED**
+- Remove all `@ts-expect-error` and `@eslint-disable`. If not avoidable, specify why with a comment. **MUST BE DISCUSSED**
+- Remove all warnings, and "normal errors" (`yarn test:lint`, `yarn test:types`, `yarn start:web`...). **MUST BE DISCUSSED**
+- Write tests for existing code if there were none. **MUST BE DISCUSSED**
+- Use `gap` instead of `<Spacer.Column />` or `<Spacer.Row />` when it is more optimal. **MUST BE DISCUSSED**
 
 Test specific:
 
+- Mock external calls, but don't mock internal parts of our code. **MUST BE DISCUSSED**
 - When you see a local variable that is over-written in every test, mock it.
 - Prefer `user` to `fireEvent`.
+- Replace `await waitFor(/* ... */)` or `await act(async () => {})` by `await screen.findByTruc()`. **MUST BE DISCUSSED**
+- Add a snapshot test for pages and modals ONLY. **MUST BE DISCUSSED: snapshots for web?**
+- Add an a11y test for the web. **MUST BE DISCUSSED**
 
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