turn rand.h into [low, high) following torch.rand pattern

[Gasoonjia]

This diff makes aoti rand shim follow torch.rand pattern to generate outputs falling into [low, high) range.
Reviewed By: GregoryComer

Differential Revision: D104723400

[pytorch-bot]

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❌ 1 New Failure, 1 Pending

As of commit bc16e82 with merge base 23a91d5 ():

NEW FAILURE - The following job has failed:

• pull / unittest-arm-backend-with-no-deps (test_pytest_models_tosa) / linux-job (gh)
  RuntimeError: Command docker exec -t c45e47002e16dbe5b9f53b859806bcf0c5aaee948dc21c4a2c6290318219efc1 /exec failed with exit code 1

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[meta-codesync]

@Gasoonjia has exported this pull request. If you are a Meta employee, you can view the originating Diff in D104723400.

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