trie.md -> trie_storage.md

docs/architecture/storage/flat_storage.md

@@ -2,7 +2,7 @@
 
 When mainnet launched, the neard client stored all the chain's state in a single
 RocksDB column `DBCol::State`. This column embeds the entire [NEAR state
-trie](./trie.md) directly in the key-value database, using roughly
+trie](./trie_storage.md) directly in the key-value database, using roughly
 `hash(borsh_encode(trie_node))` as the key to store a `trie_node`. This gives a
 content-addressed storage system that can easily self-verify.