Update README.md

Author: wangbin579

README.md

@@ -7,30 +7,42 @@ Building on the goal of enhancing MySQL scalability, this book explores various
 [Preface](Preface.md)
 
 [Part1 Problems](Part1.md)
-[Chapter 1: Traditional Methods for Solving MySQL Problems](Chapter 1.md)
-[Chapter 2: Mysterious MySQL Problems](Chapter 2.md)
+
+[Chapter 1: Traditional Methods for Solving MySQL Problems](Chapter1.md)
+
+[Chapter 2: Mysterious MySQL Problems](Chapter2.md)
 
 [Part2 Basics](Part2.md)
-[Chapter 3: How to Solve Software Problems Effectively](Chapter 3.md)
-[Chapter 4: Fundamentals of Computer Science](Chapter 4.md)
-[Chapter 5: MySQL Internals](Chapter 5.md)
-[Chapter 6: How to Scientifically Test MySQL Performance?](Chapter 6.md)
+
+[Chapter 3: How to Solve Software Problems Effectively](Chapter3.md)
+
+[Chapter 4: Fundamentals of Computer Science](Chapter4.md)
+
+[Chapter 5: MySQL Internals](Chapter5.md)
+
+[Chapter 6: How to Scientifically Test MySQL Performance?](Chapter6.md)
 
 [Part3 Analyzing and Addressing MySQL Problems](Part3.md)
-[Chapter 7: Key Improvements of MySQL 8.0 Over MySQL 5.7](Chapter 7.md)
-[Chapter 8: Refining MySQL 8.0: Next-Level Improvements](Chapter 8.md)
-[Chapter 9: Major Enhancements in Group Replication](Chapter 9.md)
-[Chapter 10: Major Improvements for MySQL Secondary Replay](Chapter 10.md)
+
+[Chapter 7: Key Improvements of MySQL 8.0 Over MySQL 5.7](Chapter7.md)
+
+[Chapter 8: Refining MySQL 8.0: Next-Level Improvements](Chapter8.md)
+
+[Chapter 9: Major Enhancements in Group Replication](Chapter9.md)
+
+[Chapter 10: Major Improvements for MySQL Secondary Replay](Chapter10.md)
 
 [Part4 Tuning](Part4.md)
-[Chapter 11: Performance Tuning](Chapter 11.md)
+
+[Chapter 11: Performance Tuning](Chapter11.md)
 
 [Part5 Conclusion](Part5.md)
-[Chapter 12: Future Directions](Chapter 12.md)
+
+[Chapter 12: Future Directions](Chapter12.md)
 
 [References](References.md)
 
 [Appendix](Appendix.md)
 
 ### Errata
-If you find any errata in the book, [please open a new issue](https://github.com/advancedmysql/The-Art-of-Problem-Solving-in-Software-Engineering_How-to-Make-MySQL-Better/issues).
+If you find any errata in the book, [please open a new issue](https://github.com/advancedmysql/The-Art-of-Problem-Solving-in-Software-Engineering_How-to-Make-MySQL-Better/issues).