Remove redundant "coding: utf-8" lines (#9786)

Part of #9744

Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.

`Signed-off-by: Jonathan de Jong <[email protected]>`

Author: ShadowJonathan

.buildkite/scripts/create_postgres_db.py

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 # Copyright 2019 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

changelog.d/9786.misc

@@ -0,0 +1 @@
+Apply `pyupgrade` across the codebase.

contrib/cmdclient/http.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

contrib/experiments/test_messaging.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts-dev/mypy_synapse_plugin.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright 2020 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts-dev/sign_json

@@ -1,6 +1,5 @@
 #!/usr/bin/env python
 #
-# -*- coding: utf-8 -*-
 # Copyright 2020 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts-dev/update_database

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 # Copyright 2019 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts/export_signing_key

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 # Copyright 2019 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts/generate_log_config

@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 
-# -*- coding: utf-8 -*-
 # Copyright 2020 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

scripts/generate_signing_key.py

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 # Copyright 2019 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");