When parsing tokens stored on the local document, first de-duplicate tokens

[six7]

We had a bug that came with #2778 that basically means we store the same token name multiple times. Basically we had an array like this:

  [
    {
        "value": "4",
        "type": "sizing",
        "name": "foo.bar"
    },
    {
        "name": "foo.bar",
        "value": "14",
        "type": "sizing"
    }
]

This is a problem! Because we will have the same token exist multiple times.

To reproduce:

• Create a token with a name foo.bar and another token with a name otherfoo.bar
• Right click the group foo and click Rename.
• Enter otherfoo.

Now if you go to packages/tokens-studio-for-figma/src/plugin/node.ts in getTokenData and add a console log to output the stored token values on line 118: console.log('Getting tokens', values, themes, activeTheme, version, tokenFormat); you will see that there's actually 2 tokens with the same name.

So, when we perform getTokenData in packages/tokens-studio-for-figma/src/plugin/node.ts, after parsing the tokens array from the document, let's de-duplicate that array and prefer the last one appearing (because likely users had been editing tokens and that's the token they've seen)

This is another reason to rather use a map-based token storage everywhere, but for this issue, let's just make sure that we fix existing user's data that's on our users documents by de-duplicating before we pass it on. This should make sure that users won't have faulty data stored.

#2778 will prohibit this from appearing in the first place but we should fix our stored data with this issue.