Add standardized template for merge request description

.gitlab/merge_request_templates/description.md

+## Related Issue(s) / Merge Request(s)
+
+<!-- Link to the related issue(s) using GitLab references, e.g., Closes #123, or link to related merge requests. -->  
+
+## Description
+
+<!-- Provide a clear and concise summary of the changes introduced in this MR. -->  
+
+## Tested Environment (e.g., radios, interfaces, CN)
+
+<!-- Describe the testing environment and steps to validate the changes.  -->  
+
+## Configuration Updates (e.g., files, parameters)
+
+<!-- List any changes to configuration files, parameters, etc. -->  
+
+## Known Issues / Limitations
+
+<!-- Mention any known issues or limitations related to this MR. -->  
+
+## Checklist
+
+* [ ] Code follows project coding standards.
+* [ ] Relevant tests have been added or updated.
+* [ ] Documentation has been updated where necessary.
+* [ ] Configuration changes have been validated in the target environment(s).
+
+## Log files or packet captures (PCAPs)
+
+<!-- Attach or reference any relevant log files or packet captures (PCAPs). -->
+
+## Additional Notes
+
+<!-- Provide any additional information or context that may be helpful for the reviewer. -->