refactor: Remove UTF-8 headers in Python files

The `# -*- coding: utf-8 -*-` headers were useful for Python 2, and
aren't needed for Python 3 where UTF-8 is the default.

yamllint support of Python 2 was dropped in early 2021, see commit
a3fc64d "End support for Python 2".

Let's drop these headers.

tests/__init__.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/common.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_braces.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_brackets.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_colons.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_commas.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_comments.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_comments_indentation.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_common.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_document_end.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_document_start.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_empty_lines.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_empty_values.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2017 Greg Dubicki
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_hyphens.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_indentation.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_key_duplicates.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_key_ordering.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2017 Johannes F. Knauf
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_line_length.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_new_line_at_end_of_file.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_new_lines.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_octal_values.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_quoted_strings.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2018 ClearScore
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_trailing_spaces.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/rules/test_truthy.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Peter Ericson
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_cli.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_config.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_linter.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_module.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2017 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_parser.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_spec_examples.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_syntax_errors.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify

tests/test_yamllint_directives.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2016 Adrien Vergé
 #
 # This program is free software: you can redistribute it and/or modify