JsDoc: Remove promise from Actor.say (#3535)

The return type of `Actor.say` contains `Promise<any>`. In TypeScript code, with the ESLint rule "@typescript-eslint/no-floating-promises" this causes lint errors for every `I.say` in the tests stating that a promise will not be awaited.
Instead, add a comment similar to many other methods (`I.see`, `I.click`, ...) and leave the return type `void`.

Author: danielrentz

lib/actor.js

@@ -16,8 +16,9 @@ class Actor {
    * add print comment method`
    * @param {string} msg
    * @param {string} color
-   * @return {Promise<any> | undefined}
    * @inner
+   *
+   * ⚠️ returns a promise which is synchronized internally by recorder
    */
   say(msg, color = 'cyan') {
     return recorder.add(`say ${msg}`, () => {