fix(try-it-out): stringify numerical initial values in ParameterRow (#4767)

* add failing tests
* coerce initial values to string
* only convert numbers to strings when setting parameter values

src/core/utils.js

@@ -780,4 +780,12 @@ export function stringify(thing) {
   }
 
   return thing.toString()
+}
+
+export function numberToString(thing) {
+  if(typeof thing === "number") {
+    return thing.toString()
+  }
+
+  return thing
 }