Simplify redundant Result/Option handling patterns

[splinter012]

This PR removes redundant code patterns in Result and Option handling, making the codebase more idiomatic and readable.

[reviewable-StarkWare]

This change is 

[orizi]

@orizi reviewed 2 of 3 files at r1, all commit messages.
Reviewable status: 2 of 3 files reviewed, 2 unresolved discussions (waiting on @splinter012)

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crates/cairo-lang-test-plugin/src/lib.rs line 267 at r1 (raw file):

                    return None;
                };
                Some((*func_id, try_extract_test_config(db, attrs).ok().flatten()?))

not better.

---

crates/cairo-lang-semantic/src/expr/compute.rs line 4817 at r1 (raw file):

            let mut data = InferenceData::new(InferenceId::NoContext);
            let mut inference = data.inference(db);
            let trait_function = db.trait_function_by_name(*trait_id, method_name).ok().flatten()?;

this isn't better.