Add missing licenses and tune the scanning workflow (#1288)

* Add missing Cumulus licenses

* Typo

* Add missing Substrate licenses

* Single job checking the sub-repos in steps

* Remove dates

* Remove dates

* Add missing (C)

* Update FRAME UI tests

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Update more UI tests

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

cumulus/polkadot-parachain/tests/purge_chain_works.rs

@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Parity Technologies (UK) Ltd.
+// Copyright (C) Parity Technologies (UK) Ltd.
 // This file is part of Substrate.
 
 // Substrate is free software: you can redistribute it and/or modify
@@ -12,7 +12,7 @@
 // GNU General Public License for more details.
 
 // You should have received a copy of the GNU General Public License
-// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+// along with Cumulus.  If not, see <http://www.gnu.org/licenses/>.
 
 use assert_cmd::cargo::cargo_bin;
 use nix::sys::signal::SIGINT;