chore: depend on public ethereum_ssz and ethereum_serde_utils crates

[morph-dev]

What was wrong?

We had dependency on private fork of ethereum_ssz and ethereum_serde_utils.

How was it fixed?

1. Adding ssz feature to alloy-primitives eliminated need for custom version of ethereum_ssz.

2. The custom function u256_from_dec_str from ethereum_serde_utils that Kolby added wasn't really needed because alloy-primitives has U256::from_str_radix(...).

3. In order for everything to work, I also needed to fork @KolbyML 's ssz_types repo and make it depend on public ethereum_ssz and ethereum_serde_utils as well (commit link).

   • Going forward, we can merge my changes into his repo, as he is more likely to keep maintaining it long term.

This leaves us with only 3 non-public repos:

• morph-dev/kolby_ssz_types - only trivial changes, we can merge them into @KolbyML 's repo
• KolbyML/tree_hash - relatively simple changes
• KolbyML/eth-trie.rs - we can leave it for now as it is and evaluate as we progress with more work on state network

To-Do

• Clean up commit history and use conventional commits.

[njgheorghita]

Nice! Looks good to me. Agreed that we should merge your ssz_types changes into @KolbyML 's repository. Whether or not that happens before or after merging this pr, I'll leave up to @KolbyML

[KolbyML]

KolbyML/ssz_types#1 I just merged this PR, cool find

[KolbyML]