fix: all renovate changes to use the same email address

At present, the default email address is used for git commits made by Renovate bots.

This is problematic, since it can change, for example after the tokenpocalypse, many bots were recreated, leading to new email addresses.

Unfortunately the new bots won't touch changes from the old bots, which is problematic.

This forces all bots to use the same email address, which can be easily identified in future.