docs: fix platform badge in readme

[mtrezza]

New Pull Request Checklist

• [x] I am not disclosing a vulnerability.
• [x] I am creating this PR in reference to an issue.

Issue Description

Platform badge in readme not rendered.

Related issue: #n/a

Approach

Fix platform badge in readme.

TODOs before merging

n/a

[parse-github-assistant[bot]]

Thanks for opening this pull request!

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[parseplatformorg]

🎉 This change has been released in version 2.0.0