Update README: bump latest versions

Update README.md to bump the 'Latest Version' entries for branches: main from 0.2.19 to 0.2.20 and 1.x from 0.1.19 to 0.1.20 so the documentation matches the released package versions.

Author: mercyblitz

README.md

@@ -110,8 +110,8 @@ Choose the version that matches your Spring Boot generation:
 
 | Branch | Spring Boot Compatibility | Latest Version |
 |--------|---------------------------|----------------|
-| `main` | 3.0.x – 3.5.x, 4.0.x      | `0.2.19`       |
-| `1.x`  | 2.0.x – 2.7.x             | `0.1.19`       |
+| `main` | 3.0.x – 3.5.x, 4.0.x      | `0.2.20`       |
+| `1.x`  | 2.0.x – 2.7.x             | `0.1.20`       |
 
 ### Add Module Dependencies