docs: more update to dev instructions

Author: soedirgo

README.md

@@ -94,7 +94,7 @@ None. Please don't use this as a standalone server. This should be used behind a
 
 To start developing, run `npm run dev`. It will set up the database with Docker for you. The server will restart on file change.
 
-To test your changes, run `npm run test`. To review your changes, add the `-u/--updateSnapshot` flag to `jest` on the `test:run` script, run `npm run test`, and then review the git diff of the snapshots. Don't forget to remove the `-u/--updateSnapshot` flag when committing.
+If you are fixing a bug, you should create a new test case. To test your changes, add the `-u/--updateSnapshot` flag to `jest` on the `test:run` script, run `npm run test`, and then review the git diff of the snapshots. Depending on your change, you may see `id` fields being changed - this is expected and you are free to commit it, as long as it passes the CI. Don't forget to remove the `-u/--updateSnapshot` flag when committing.
 
 ## Licence