chore(crypto): CRP-2579 In basic_ethereum example use ic_crypto_secp256k1

[randombit]

This crate has the same derivation functionality of extended_bip32, but does not rely on the threshold signature implementation. Thus it has far fewer dependencies (as can be seen in the Cargo.lock update).

The extended_bip32 crate is being removed in https://github.com/dfinity/ic/pull/1172