Fix OSS import for ref_implementations

[DrJessop]

Summary: Was using buck-based loading of quantized decomposed in ref_implementations which isn't CMake-compatible. This fixes that approach.

Differential Revision: D88303133

[pytorch-bot]

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✅ You can merge normally! (1 Unrelated Failure)

As of commit 6d4869d with merge base e74f1d3 ():

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / android / run-emulator (gh) (trunk failure)
  Timeout waiting for emulator to boot.

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[meta-codesync]

@DrJessop has exported this pull request. If you are a Meta employee, you can view the originating Diff in D88303133.

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