Update changelog and warn of breaking change in minor version.

Author: aldas

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v4.2.1 - 2024-12-04
+
+**Enhancements**
+
+* Return HTTP status 400 if missing JWT by @kitloong in [13](https://github.com/labstack/echo-jwt/pull/13)
+* Update dependencies, CI flow etc. by @aldas in [21](https://github.com/labstack/echo-jwt/pull/21)
+* Update dependencies, CI flow, README etc. by @aldas in [24](https://github.com/labstack/echo-jwt/pull/24)
+* Improve readme formatting by @aldas in [25](https://github.com/labstack/echo-jwt/pull/25)
+
+
 ## v4.2.0 - 2023-01-26
 
 **Breaking change:** [JWT](github.com/golang-jwt/jwt) has been upgraded to `v5`. Check/test all your code involved with JWT tokens/claims. Search for `github.com/golang-jwt/jwt/v4` 

README.md

@@ -14,6 +14,9 @@ as JWT implementation.
 This repository does not use semantic versioning. MAJOR version tracks which Echo version should be used. MINOR version
 tracks API changes (possibly backwards incompatible) and PATCH version is incremented for fixes.
 
+NB: When `golang-jwt` MAJOR version changes this library will release MINOR version with **breaking change**. Always 
+add at least one integration test in your project.
+
 For Echo `v4` use `v4.x.y` releases.
 Minimal needed Echo versions:
 * `v4.0.0` needs Echo `v4.7.0+`