build(deps): bump third-party/FFmpeg/AMF from 3588c60 to 681af0d

Bumps [third-party/FFmpeg/AMF](https://github.com/GPUOpen-LibrariesAndSDKs/AMF) from `3588c60` to `681af0d`.
- [Release notes](https://github.com/GPUOpen-LibrariesAndSDKs/AMF/releases)
- [Commits](GPUOpen-LibrariesAndSDKs/AMF@3588c60...681af0d)

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

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