Update releases information

The list didn't include the latest 4.2 release, indicating that 4.0 is still a supported version

Author: xammmue

extra/releases.md

@@ -12,16 +12,17 @@ For example:
 - versions 3.4 has been released on 18 September 2024;
 - versions 4.0 has been released on 27 September 2024;
 - versions 4.1 has been released on 28 February 2025;
+- versions 4.2 has been released on 18 September 2025;
 
 ## Maintenance
 
 3 versions are maintained at the same time:
 
-- **stable** (currently the **4.1** branch): regular bugfixes are integrated in this version
-- **old-stable** (are the last branch: **4.0**): [security fixes](security.md) are integrated in this version, regular bugfixes are **not** backported in it
+- **stable** (currently the **4.2** branch): regular bugfixes are integrated in this version
+- **old-stable** (are the last branch: **4.1**): [security fixes](security.md) are integrated in this version, regular bugfixes are **not** backported in it
 - **development** (**main** branch): new features target this branch
 
-Older versions (1.x, 2.6..., 3.0...) **are not maintained**. If you still use them, you must upgrade as soon as possible.
+Older versions (1.x, 2.6..., 3.0..., 4.0) **are not maintained**. If you still use them, you must upgrade as soon as possible.
 
 The **old-stable** branch is merged in the **stable** branch on a regular basis to propagate [security fixes](security.md).
 The **stable** branch is merged in the **development** branch on a regular basis to propagate [security](security.md) and regular bugfixes.