[tests] migrate from jest to vitest (#3940)

This is a big change, but I think it's a good move, as `vitest` is much
more modern than `jest`.

I'm excited about the UI watch feature (run `npm run test:ui`), for
example - it's really helpful and saves time when debugging tests. I had
to adjust a few tests because they had time related issues, but
basically we are now testing the same things - even a bit better and
less flaky (I hope).

What do you think?

js/utils.js

@@ -34,7 +34,7 @@ module.exports = {
 			].join("\n");
 			Log.info(systemDataString);
 
-			// Return is currently only for jest
+			// Return is currently only for tests
 			return systemDataString;
 		} catch (error) {
 			Log.error(error);
@@ -65,8 +65,10 @@ module.exports = {
 				if (results && results.length > 0) {
 					// get the position parts and replace space with underscore
 					const positionName = results[1].replace(" ", "_");
-					// add it to the list
-					modulePositions.push(positionName);
+					// add it to the list only if not already present (avoid duplicates)
+					if (!modulePositions.includes(positionName)) {
+						modulePositions.push(positionName);
+					}
 				}
 			});
 			try {