GitHub Action to keep offsetReduction branch up to date (#1149)
GitHub Action to keep offsetReduction branch up to date (#1149)

## Technical Description

This PR adds a github action that merges the changes to `master` automatically into the `offsetReduction` branch provided to Joerg Behrens from the DKRZ. It triggers each time the `master` branch is updated. 



MeteoSwiss-APN/dawn,MeteoSwiss-APN/dawn,MeteoSwiss-APN/dawn