v3.0.0-rc3

[DevOps] Mark release as prerelease if there's a version suffix available
[DevOps] GHA(deps): Bump smartsquaregmbh/delete-old-packages from 0.3.1 to 0.3.3
[DevOps] Allow prerelease versions in choco package
[DevOps] Fixed 'The format of value Wyam2 wyam release' is invalid.' in the Release cake target

Please see https://wyam2.github.io/docs/usage/obtaining for important notes about downloading and installing.