build(deps): bump third-party/FFmpeg/Vulkan-Loader

Bumps [third-party/FFmpeg/Vulkan-Loader](https://github.com/KhronosGroup/Vulkan-Loader) from `a9e72c6` to `506124c`.
- [Commits](KhronosGroup/Vulkan-Loader@a9e72c6...506124c)

---
updated-dependencies:
- dependency-name: third-party/FFmpeg/Vulkan-Loader
  dependency-version: 506124c4ac349c7a515ab71fdd460f285fae71bd
  dependency-type: direct:production
...

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Author: dependabot[bot]