test(trie): narrow the range of keys for sparse trie fuzz

[shekhirin]

Basically this:

reth/crates/trie/sparse/src/trie.rs

Lines 1222 to 1232 in c218629

	updates in proptest::collection::vec(
	proptest::collection::hash_map(
	// Having only the first 3 nibbles set, we narrow down the range of keys
	// to 4096 different hashes. It allows us to generate collisions more likely
	// to test the sparse trie updates.
	arbitrary_with::<Nibbles, _, _>(SizeRange::new(3..=3)),
	any::<Vec<u8>>(),
	1..100,
	),
	1..100,
	)

Allows us to have more updates and deletions in the trie.

[rkrasiuk]

great