Updates name and links in contributor files for Lucy Macartney

[lmac-1]

I realised my name on GitHub wasn't my actual full name 😅. I've just updated it now and made the following updates on this pull request in all files related to contributors:

• Updates Lucy Mac to Lucy Macartney
• Adds the content link to my blog on hashnode on content icon
• Updates my link from LinkedIn to my GitHub profile

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Name	Link
🔨 Latest commit	e7c51efe0dd7855ec0a5f01ea729690938aa040f