[otomads] Add new extractor per #14387

[f4188]

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• At least skimmed through adding new extractor tutorial and youtube-dl coding conventions sections
• Searched the bugtracker for similar pull requests
• Checked the code with flake8

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What is the purpose of your pull request?

• Bug fix
• Improvement
• New extractor
• New feature

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Description of your pull request and other information

Add new extractor for otomads.com