Added blog post: Your guide to solidjs user authentication

[FuzzySid]

Checklist

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• [x] You created a branch from develop branch.
• [x ] You PR is raised on develop branch and not onmain.
• [x ] Blog follows Blog Guidelines.
• [x ] You have read the Contribution Guidelines before creating this PR.
• [x] Checked for any duplicate blog entry.
• [x] Checked for all grammatical errors in the blog.
• [x] You have not published the blog content elsewhere on the internet on platforms like Medium, Dev.to, etc.
• [x] The content is not copy-pasted from elsewhere on the internet.

Description of Change