Delete existing release asset before releasing

[ekangmonyet]

We're using only one tag for release (latest), so we have to either replace it correctly or delete it before uploading, otherwise it will fail (https://github.com/ekangmonyet/lkmpg/runs/3213455232):

Error: Validation Failed: {"resource":"ReleaseAsset","code":"already_exists","field":"name"}

One possible solution is to use mknejp/delete-release-assets to delete existing asset. If action-gh-release supports upserting (softprops/action-gh-release#134), this should only be a temporary remedy. Warning from the delete-release-assets repository:

WARNING
Because this action has the power to delete any asset from any release in the repository (via the access token) be extra careful that you specify the correct tag!

Since it is not really urgent, we may wait for the patch for action-gh-release as well.