pull_request_template.md

Description

relates to #1234

Issue was linked above
No generated code was adjusted manually
Changelogs
- Changelog in the root directory was adjusted
- Changelog(s) of the service(s) were adjusted
VERSION file(s) of the service(s) were adjusted
Code format was applied: make fmt
Examples were added / adjusted (see examples/ directory)
Unit tests got implemented or updated
Unit tests are passing: make test (will be checked by CI)
No linter issues: make lint (will be checked by CI)