Database download should implement cascading permissions

[simonw]

datasette/datasette/views/database.py

Lines 130 to 136 in 5a15197

	class DatabaseDownload(DataView):
	name = "database_download"
	async def view_get(self, request, database, hash, correct_hash_present, **kwargs):
	await self.check_permission(request, "view-instance")
	await self.check_permission(request, "view-database", database)
	await self.check_permission(request, "view-database-download", database)

Should be updated for #832 cascading permissions. Example commit: d6e03b0

[simonw]

Example:

datasette/datasette/views/database.py

Lines 26 to 32 in 5a15197

	await self.check_permissions(
	request,
	[
	("view-database", database),
	"view-instance",
	],
	)