[package.json] Add ./package.json to exports

[hatem-72]

This PR fixes the compatibility between react-native and the last luxon versions (broken since v2.5.0).

It adds the package.json to the exports section

  "exports": {
    ".": {
      "import": "./src/luxon.js",
      "require": "./build/node/luxon.js"
    },
+   "./package.json": "./package.json",
  },

It is something you can find in other popular libraries that have to deal with multiple js environments and bundlers, such as react-native. Something similar happened to the uuidjs/uuid repository:

• Issue
• PR
• Release
• Source code now

This PR will close https://github.com/moment/luxon/issues/1238

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[gbinu42]

Hi @icambron can this be merged?

[dminkovsky]

Just merged the same fix here: https://github.com/nhost/nhost/pull/828.

[cglacet]

I believe the bug is still here in version 3.0.1.

[icambron]

I don't understand what this does, but I don't see an issue with exporting package.json

[cglacet]

@icambron if you don't modify the file as suggested here it gives the following error :

warn Package luxon has been ignored because it contains invalid configuration. 
Reason: Package subpath './package.json' is not defined by "exports" in /Users/project/node_modules/luxon/package.json