feat(workflows-sdk): Allow a step to not define an expected input (#5775)

**What**
Allow a step to not define an expected input, previously even if no input was expected, an object was always expected to be passed to the stepFunction inside the workflow composition. Now
```ts
const stepWithoutArgs = createStep("step1", () => {
  return new StepResponse("string")
})

const stepWithoutExepectedInput = createStep("step2", (_: {}, context) => {
  console.log("input", _) // {}
  return new StepResponse("string")
})

const workflow = createWorkflow("workflow1", () => {
  stepWithoutArgs()
  return stepWithoutExepectedInput()
})

workflow()
  .run()
  .then((res) => {
    console.log(res.result) // string
  })
```

packages/workflows-sdk/package.json

@@ -39,6 +39,7 @@
     "prepublishOnly": "cross-env NODE_ENV=production tsc --build",
     "build": "rimraf dist && tsc --build",
     "watch": "tsc --build --watch",
-    "test": "jest --runInBand --bail --forceExit"
+    "test": "jest --runInBand --bail --forceExit",
+    "test:run": "../../node_modules/.bin/ts-node ./src/utils/_test.ts"
   }
 }