Add minimum_length to extended header for BC

[pytorchbot]

Summary:
Error happening when we have older PTE files with extended header size 24.

When we call 'from_bytes', we expect header size 32 after adding segment_data_size field.

This is BC on C++ side because we have a minimum length.
Add minimum length to python to make the change BC.

Differential Revision: D82492169

[pytorch-bot]

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❌ 2 Cancelled Jobs, 1 Unrelated Failure

As of commit 19fa0ec with merge base 10e93fb ():

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• pull / unittest / macos / macos-job (gh)
  ##[error]The operation was canceled.
• pull / unittest-editable / macos / macos-job (gh)
  ##[error]The operation was canceled.

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

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

• pull / test-openvino-linux / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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