Make updating snapshots a conscious decision

With -u, we simply accept the result of any change we make that changes the outcome of any of our snapshot tests.
To spot issues easly, let the tests fail on failing snapshot tests, instead of noticing changes to snapshot files
when you are ready to commit your changes.

packages/js/package.json

@@ -4,7 +4,7 @@
   "license": "GPL-3.0",
   "private": true,
   "scripts": {
-    "test": "jest -u",
+    "test": "jest",
     "lint": "eslint src tests --max-warnings=74"
   },
   "dependencies": {