RTK createAsyncThunk typing recipes

 ### Recipes for typing createAsyncThunk

  // Typing with Generics
  const withGenerics = createAsyncThunk<
    { banana: string },
    string,
    { state: RootState }
  >('test/usingGenerics', (arg, { getState }) => {
    const { test } = getState()
    return {
      banana: 'test'
    }
  })

  // Generic typing and allowing an optional arg
  const withOptionalArg = createAsyncThunk<
    { banana: string },
    string | void,
    { state: RootState }
  >('test/withOptionalArg', (arg, { getState }) => {
    const { test } = getState()
    if (arg) {
        // Do something with the arg if it exists
    }

    return {
      banana: 'test'
    }
  })

  // Inline typing with an optional arg
  const withOptionalArgInline = createAsyncThunk('test/withOptionalArgInline', (arg: string | void, { getState }) => {
    const { test } = getState() as RootState
    return {
      banana: 'test'
    }
  })

  // Unused arg, but has access to thunkApi
  const optionalWithGetState = createAsyncThunk('test/optionalWithGetState', (_: void, thunkApi) => {
    const { test } = thunkApi.getState() as RootState
    // Do something with the state here, make an api request, etc.
    return {
      banana: 'test'
    }
  })