fix lint issue with comment

Author: peterargue

engine/access/rpc/backend/backend_transactions.go

@@ -350,11 +350,15 @@ func (b *backendTransactions) GetTransactionResult(
 	return txResult, nil
 }
 
-// retrieveBlock function returns a block based on the input argument. The block ID lookup has the highest priority,
-// followed by the collection ID lookup. If both are missing, the default lookup by transaction ID is performed.
+// retrieveBlock function returns a block based on the input arguments.
+// The block ID lookup has the highest priority, followed by the collection ID lookup.
+// If both are missing, the default lookup by transaction ID is performed.
+//
+// If looking up the block based solely on the txID returns not found, then no error is returned.
+//
+// Expected errors:
+// - storage.ErrNotFound if the requested block or collection was not found.
 func (b *backendTransactions) retrieveBlock(
-// the requested block or collection was not found. If looking up the block based solely on the txID returns
-// not found, then no error is returned.
 	blockID flow.Identifier,
 	collectionID flow.Identifier,
 	txID flow.Identifier,