Use BtreeMap for block numbers

[mattsse]

for use cases like

#10037

it is beneficial to have the block numbers in canonical order

currently we're using a regular hashmap:

reth/crates/chain-state/src/in_memory.rs

Lines 30 to 31 in 29dc8fc

	/// Mapping of block numbers to block hashes.
	numbers: RwLock<HashMap<u64, B256>>,

we can easily find the lowest and highest block with a btreemap

TODO

• replace hashmap with betreemap