Embeds: Remove Someecards from the oEmbed provider allow list

[elphizu]

The Someecards oEmbed endpoint now returns a 404 response, and card pages no longer advertise an oEmbed discovery link.

This removes the provider patterns for someecards.com and some.ly from the oEmbed allow list and documents Someecards as no longer supported as of WordPress 7.1.1.

Trac ticket: https://core.trac.wordpress.org/ticket/66078

Use of AI Tools

AI assistance: Yes
Tool(s): OpenAI Codex
Model(s): GPT-5.6 Sol light
Used for: Identifying the relevant code path, final implementation were reviewed and edited by me.

[github-actions]

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[github-actions]

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Props suryakantupadhyay.

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