For major release

Add new SPDX License list data

For release for new GHC version:

Update GHC flags in normaliseGhcArgs, and add the GHC version to supportedGHCVersions (Distribution.Simple.Program.GHC)
Update Language.Haskell.Extension list, if there are new GHC extensions
Update setupMinCabalVersionConstraint (in Distribution.Client.ProjectPlanning)