PWA Module Adds Trailing Comma to End of manifest.webmanifest

[joshasbury]

Generated code looks like this:
`{
"name": "Example",
"short_name": "Example",
"lang": "en-us",
"display": "fullscreen",
"orientation" : "portrait",
"start_url": "http://localhost:1313/?utm_source=web_app_manifest",
"background_color": "#fff",
"theme_color": "#000",

}`

Note that there are also additional carriage returns following the unnecessary comma.

[tfsomrat]

Thanks because you don't have a favicon for your site. Add a valid favicon source to your params.toml file. it will solve the issue.