Add more conflict types to ConflictFinder

[grasphoper]

📝 Summary

Add more conflict types to ConflictFinder as per #226

A brief overview of the changes:

• I added multiple new mapping entries to ConflictFinder, namely

    group_balance_reads: HashMap<Address, Vec<usize>>,
    group_balance_writes: HashMap<Address, Vec<usize>>,
    group_contract_creations: HashMap<Address, Vec<usize>>,
    group_contract_destructions: HashMap<Address, Vec<usize>>,

• Added conflicts that can be related to those fields
• Added combine_groups - a utility fn to reuse code
• Added ConflictFinder.add_group_to_index and ConflictFinder.remove_group_from_index to reuse code and improve readability; index here means search index, or different member mappings of ConflictFinder

---

✅ I have completed the following steps:

• Run make lint
• Run make test
• Added tests (if applicable)

[grasphoper]

For anyone reviewing, please take a look at TODO comments I left and let me know what you think!

[ZanCorDX]

The original code had some copy/paste (our bad!) but you may avoid it.
Example:
on remove_group_from_index you can create a fn like:

    fn remove_group_from_map<K: std::cmp::Eq + std::hash::Hash + Clone>(
        group_id: usize,
        key_to_group: &mut HashMap<K, Vec<usize>>,
        keys: &Vec<K>,
    ) {
        for key in keys {
            let groups = key_to_group.entry(key.clone()).or_default();
            if let Some(idx) = groups.iter().position(|el| *el == group_id) {
                groups.swap_remove(idx);
            }
        }
    }

And just call it 6 times.
The same goes for add (maybe somewhere else?).

[ZanCorDX]

About the TODO ideas:
1- We could change HashMap to BTreeMap ensuring that SlotKey's ordering compares Address first. Posible con: BTreeMap could be expensive.
2- Use nested HashMaps. The first level for address and the second level for key.
This way we don't get redundant structures.

[grasphoper]

@ZanCorDX thank you for all your suggestions. I implemented them and just pushed updated code! Went with a 2-layer HashMap as the "address conflict checking" solution.

[grasphoper]

Hi @ZanCorDX . Any more changes you would want to this?