FEAT: Redirect output to another file.

[eskopp]

Is your feature request related to a problem? Please describe.
The basic problem is that the workflow looks very good but I'm frustrated that it's so big, so I put it in a linked readme in my special repo. Unfortunately it can`t write to the waka.md.

Describe the solution you'd like
There should be an option to specify with with: in which file the content should be written. Readme.md can be set by default. It would be very helpful for me.

Describe alternatives you've considered
This is not applicable as the feature does not exist. I tried to put the area block in another file and hoped that the workflow would find it. Unfortunately this was not the case.

Additional context
Please :)

Example:

name: Waka Readme

on:
  workflow_dispatch:
  schedule:
    - cron: "0 0 * * *"

jobs:
  update-readme:
    name: Update this repos README
    runs-on: ubuntu-latest
    steps:
      - uses: anmol098/waka-readme-stats@master
        with:
          WAKATIME_API_KEY: ${{ secrets.WAKATIME_API_KEY }}
          GH_TOKEN: ${{ secrets.GH_TOKEN }}
          SHOW_PROJECTS: "False"
          SHOW_LINES_OF_CODE: "False"
          SHOW_LOC_CHART: "False"
          LOCALE: "en"
          OUTPUT_FILE: "waka.md"