[COPYING] Another update

Adobe, Inc has copyright in src/hb-subset-cff*, test/api/test-subset*, and
misc other places.

Ebrahim Byagowi has copyright as far back as 2015 in places like
src/hb-directwrite.cc.

Google, Inc has newer copyright into 2022 in places like
src/graph/test-classdef-graph.cc. Also, listing every year was getting a bit
unwieldy, so just do 2010-2022.

Igalia S.L. contributed the stuff in src/hb-ot-math*.

The only references I could find to Martin Hosken & SIL were in
src/hb-graphite2*, and they were 2011, not 2009.

Mozilla's got a bunch of 2015 code in src/hb-ot-shaper-*.

Red Hat has copyright up to 2023 (eg, test/api/test-glyph-names.c).

COPYING

@@ -2,21 +2,23 @@ HarfBuzz is licensed under the so-called "Old MIT" license.  Details follow.
 For parts of HarfBuzz that are licensed under different licenses see individual
 files names COPYING in subdirectories where applicable.
 
-Copyright © 2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020  Google, Inc.
+Copyright © 2010-2022  Google, Inc.
-Copyright © 2018,2019,2020  Ebrahim Byagowi
+Copyright © 2015-2020  Ebrahim Byagowi
 Copyright © 2019,2020  Facebook, Inc.
-Copyright © 2012  Mozilla Foundation
+Copyright © 2012,2015  Mozilla Foundation
 Copyright © 2011  Codethink Limited
 Copyright © 2008,2010  Nokia Corporation and/or its subsidiary(-ies)
 Copyright © 2009  Keith Stribley
-Copyright © 2009  Martin Hosken and SIL International
+Copyright © 2011  Martin Hosken and SIL International
 Copyright © 2007  Chris Wilson
 Copyright © 2005,2006,2020,2021,2022,2023  Behdad Esfahbod
 Copyright © 2005  David Turner
-Copyright © 2004,2007,2008,2009,2010  Red Hat, Inc.
+Copyright © 2004,2007,2008,2009,2010,2013,2021,2022,2023  Red Hat, Inc.
 Copyright © 1998-2004  David Turner and Werner Lemberg
+Copyright © 2016  Igalia S.L.
 Copyright © 2022  Matthias Clasen
 Copyright © 2018,2021  Khaled Hosny
+Copyright © 2018,2019,2020  Adobe, Inc
 
 For full copyright notices consult the individual files in the package.