Update CHANGELOG.md with Docker tagging policy and Makefile reorganis…

…ation

This commit updates the CHANGELOG.md to reflect two significant improvements:
- The adoption of a unified policy for tagging Docker images, addressing
  issue 320. This change ensures consistency in how Docker images are
  tagged across the project, facilitating easier management and deployment
  of images.
- The reorganisation of deployment Makefiles as part of issue 385. This
  enhancement aims at better documenting the deployment process and
  simplifying the management of deployment scripts. The new structure of
  Makefiles contributes to a more streamlined and understandable
  deployment process.

These updates are part of ongoing efforts to enhance the deployment
process by refining project documentation and operational scripts.

CHANGELOG.md

@@ -46,6 +46,8 @@ changes.
 - Adjusted Nix configuration to meet projects needs [Issue 187](https://github.com/IntersectMBO/govtool/issues/187).
 - Integrated OAuth to securely notify about deployment status in Slack [Issue 194](https://github.com/IntersectMBO/govtool/issues/194).
 - Streamlined the application build and deployment process, thereby accelerating continuous delivery (CD) and reducing the resource burden [Issue 246](https://github.com/IntersectMBO/govtool/issues/246).
+- Applied unified policy on Docker images tagging [Issue 320](https://github.com/IntersectMBO/govtool/issues/320).
+- Reorganised deployment Makefiles in order to better document the process and easier management [Issue 385](https://github.com/IntersectMBO/govtool/issues/385).
 
 ### Removed
 -