[ruff] add fix safety section (RUF007)

[VascoSch92]

The PR add the fix safety section for rule RUF007 (#15584 )

It seems that the fix was always marked as unsafe #14401

Unsafety example

This first example is a little extreme. In fact, the class Foo overrides the __getitem__ method but in a very special, way. The difference lies in the fact that zip(letters, letters[1:]) call the slice letters[1:] which is behaving weird in this case, while itertools.pairwise(letters) call just __getitem__(0), __getitem__(1), ... and so on.

Note that the diagnostic is emitted: playground

I don't know if we want to mention this problem, as there is a subtile bug in the python implementation of Foo which make the rule unsafe.

from dataclasses import dataclass
import itertools

@dataclass
class Foo:
    letters: str
    
    def __getitem__(self, index):
        return self.letters[index] + "_foo"


letters = Foo("ABCD")
zip_ = zip(letters, letters[1:])
for a, b in zip_:
    print(a, b) # A_foo B, B_foo C, C_foo D, D_foo _
    
pair = itertools.pairwise(letters)
for a, b in pair:
    print(a, b) # A_foo B_foo, B_foo C_foo, C_foo D_foo

This other example is much probable.
here, itertools.pairwise was shadowed by a costume function (playground)

from dataclasses import dataclass
from itertools import pairwise

def pairwise(a):
    return []
    
letters = "ABCD"
zip_ = zip(letters, letters[1:])
print([(a, b) for a, b in zip_]) # [('A', 'B'), ('B', 'C'), ('C', 'D')]

pair = pairwise(letters)
print(pair) # []

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[VascoSch92]

@dylwil3 Hey ;-) I think it is ready to review

[VascoSch92]

@ntBre , @dylwil3 let me know what do you think :-)

[ntBre]

Thanks! And nice catch on the slicing behavior. That is very tricky.