fix(corelib): Add missing impl for type conversions between U256

[lambda-0x]

This change is 

[spapinistarkware]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on @lambda-0x)

---

corelib/src/integer.cairo line 1572 at r1 (raw file):

    }
}

Wdyt about adding all the others

---

corelib/src/integer.cairo line 1454 at r2 (raw file):

}

// impls for (where X > 8):

I think it's better without these comments.
The impl signature is clear enough.

[lambda-0x]

Wdyt about adding all the others

which other are missing?

[spapinistarkware]

Reviewed 1 of 1 files at r3, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lambda-0x)

[orizi]

Reviewed 1 of 1 files at r3, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lambda-0x)

[lambda-0x]

CI is failing due to this file having:

cairo/tests/bug_samples/issue3211.cairo

Lines 6 to 15 in d448693

	impl U256TryIntoU64 of TryInto<u256, u64> {
	#[inline(always)]
	fn try_into(self: u256) -> Option<u64> {
	if (self.high == 0) {
	self.low.try_into()
	} else {
	Option::None(())
	}
	}
	}

Which causes there to be duplicate implementation error, what should i do with the duplicate impl in that test?

[spapinistarkware]

Be explicit when using this impl.

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lambda-0x)

[spapinistarkware]

i.e. refer to the specific impl by name

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lambda-0x)

[lambda-0x]

the problem is both have the same name, should rename the one used in test something else @spapinistarkware?

they are essentially the same impl as well but in there its used to test some compiler branching issue, so removing it wouldn't make sense.

[spapinistarkware]

You don't have to rename, it shadows the core one. u can rename if u want.

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @lambda-0x)