Update metadata doc

[alfetopito]

Summary

There are small changes to the affiliate doc, which require changes to https://github.com/gnosis/cowswap/blob/develop/src/custom/utils/metadata.ts#L26-L50

• Set the version fields to 0.1.0
• Remove kind
• Rename inner referrer property to address

Example:

{
  "version": "0.1.0",
  "appCode": "CowSwap",
  "metadata": { 
    "referrer": {
      "version": "0.1.0",
      "address": "0x424a46612794dbb8000194937834250Dc723fFa5"
    }
  }
}

[ramirotw]

@alfetopito there was already a ticket and PR (#1190) for this that wasn't merged. I'll take care of resolving the conflicts and let the bot merge it

[alfetopito]

Ah thanks Ramiro, completely forgot about it :)

I'll close this one as a duplicate