Add Banuba Video Editor SDK

[GlebPBanuba]

Please read How to contribute before creating a submission.

Description

Video Editor SDK (Android & iOS) is a fully-functional video editor that can be integrated into an app in minutes, designed to create exciting social media content with a wide range of effects and filters for professional-quality videos on phones. https://github.com/Banuba/ve-sdk-flutter-integration-sample

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Checklist

• [x] I read How to contribute
• [x] I edited the SOURCE.md file only
• [x] Added a link to the repo in the PR

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[KollerWithDoris]

这是来自QQ邮箱的假期自动回复邮件。您好，我最近正在休假中，无法亲自回复您的邮件。我将在假期结束后，尽快给您回复。

[mcosti]

This is a paid SDK (and a very expensive one)