Add a helper task for the installer

So it matches the rest of the Solid lineup

lib/tasks/solid_cable_tasks.rake

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+desc "Copy over the schema and set cache for Solid Cable"
+namespace :solid_cable do
+  task :install do
+    Rails::Command.invoke :generate, [ "solid_cable:install" ]
+  end
+end