build(deps): bump third-party/FFmpeg/FFmpeg from ec78e95 to abb609b

Bumps [third-party/FFmpeg/FFmpeg](https://github.com/FFmpeg/FFmpeg) from `ec78e95` to `abb609b`.
- [Commits](FFmpeg/FFmpeg@ec78e95...abb609b)

---
updated-dependencies:
- dependency-name: third-party/FFmpeg/FFmpeg
  dependency-version: abb609bb5864beb39faaf109cb0187250d4659e1
  dependency-type: direct:production
...

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Author: dependabot[bot]