chore: remove unused _name param from create_impl_generics

[Galoretka]

This function didn’t use the name parameter and it was explicitly prefixed with _, indicating it was dead weight. The function is private and only used in this module, so changing the signature is safe. Updated the two call sites to pass just generics

[reviewable-StarkWare]

This change is 

[orizi]

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @Galoretka)

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crates/cairo-lang-proc-macros/src/debug.rs line 46 at r1 (raw file):

    // a) impl-side generics  = original + 'a + T
    let impl_generics = create_impl_generics(name, generics);

rather keep it consistent with the rest of the items.