fix: replace toString with String in switch blocks

Prevents the switch costume to (), switch backdrop to (), and switch backdrop to () and wait blocks from hanging indefinitely in certain situations

Author: OceanIsEndless

packages/scratch-vm/src/blocks/scratch3_looks.js

@@ -392,7 +392,7 @@ class Scratch3LooksBlocks {
             target.setCostume(optZeroIndex ? requestedCostume : requestedCostume - 1);
         } else {
             // Strings should be treated as costume names, where possible
-            const costumeIndex = target.getCostumeIndexByName(requestedCostume.toString());
+            const costumeIndex = target.getCostumeIndexByName(String(requestedCostume));
 
             if (costumeIndex !== -1) {
                 target.setCostume(costumeIndex);
@@ -426,7 +426,7 @@ class Scratch3LooksBlocks {
             stage.setCostume(optZeroIndex ? requestedBackdrop : requestedBackdrop - 1);
         } else {
             // Strings should be treated as backdrop names where possible
-            const costumeIndex = stage.getCostumeIndexByName(requestedBackdrop.toString());
+            const costumeIndex = stage.getCostumeIndexByName(String(requestedBackdrop));
 
             if (costumeIndex !== -1) {
                 stage.setCostume(costumeIndex);