[WorkManager] Better Kotlin DSL for Data

[EdricChan03]

val workData = buildData {
  // Perhaps we can have similar utilities to that of a MutableMap?
  this += "key" to 123
  this += workDataOf(/* ... */) // Add existing data
  addData {
    // Add data from a Data.Builder
    putBoolean("abc", false)
  }

  this -= workDataOf(/* ... */) // Remove the mutable data's properties that are present in the specified Data
}