Add TestLessThan hint.

[ilyalesokhin-starkware]

This change is 

[orizi]

Reviewed 7 of 7 files at r1, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @ilyalesokhin-starkware)

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crates/runnair/src/utils.rs line 4 at r1 (raw file):

use stwo_prover::core::fields::m31::M31;
// use stwo_prover::core::fields::qm31::QM31;

this doesn't break anything?

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crates/runnair/src/vm/hints.rs line 39 at r1 (raw file):

        rhs: ResOperand,
        dst: CellRef,
    },

can AllocateSegment be supported?

[orizi]

Reviewed all commit messages.
Reviewable status: 4 of 8 files reviewed, 1 unresolved discussion (waiting on @ilyalesokhin-starkware)

[orizi]

Reviewed 1 of 4 files at r2, 3 of 4 files at r3, all commit messages.
Reviewable status: 8 of 9 files reviewed, 1 unresolved discussion (waiting on @ilyalesokhin-starkware)