Unable to modify location of on-screen Velocity html reporter button

I need to change the on-screen location of the Velocity HTML reporter button. According to the docs, one can achieve this by inserting the following in a settings.json file:

  "public": {
    "velocity:html-reporter": {
      "position": "bottom right",
      "tab-index" : 1

I inserted this into a settings.json file in the root directory of my app but it had no impact. Is there something I’m missing?