Fix Typo

Author: zohairawan

src/SUMMARY.md

@@ -481,7 +481,7 @@ battleship
   - [Subpackages](./packages/subpackages.md)
   - [Reverse Domain Name Notation](./packages/reverse_domain_name_notation.md)
 
-# Data Types IV
+# Data Types V
 
 - [Records](./records.md)
   - [Declaration](./records/declaration.md)