Fix whitespace in JSON.stringify indentation

[pre-martin]

"4 times empty string" looks like an error. To properly indent the manifest file after sanitizing it, either the number 4 or 4 spaces are required (or any other value or string).

See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#space for the details of JSON.stringify()

[GeekyEggo]

Hey Martin, this does indeed look to be an error, thanks for bringing it to our attention.

I notice this PR uses spaces, however the pack command is already using tabs (\t) elsewhere.

cli/src/commands/pack.ts

Line 198 in 19caf04

write(JSON.stringify(manifest, undefined, "\t"));

To remove the age-old “spaces vs tabs” debate, we’re going to introduce better format detection (and retention) of the manifest file. 👍

[pre-martin]

Thanks for pointing that out. I didn't notice the formatting in the "version" method.

The worst thing is when tabs and spaces are mixed within the same file. That's why I've prepared an alternative pull request: #63