Add documentation for messages with anomalous in their name

Co-authored-by: Vladyslav Krylasov <[email protected]>

Author: DanielNoord

doc/data/messages/a/anomalous-backslash-in-string/bad.py

@@ -0,0 +1 @@
+string = "\z"  # [anomalous-backslash-in-string]

doc/data/messages/a/anomalous-backslash-in-string/good.py

@@ -0,0 +1,2 @@
+string = r"\z"
+string = "\n"

doc/data/messages/a/anomalous-unicode-escape-in-string/bad.py

@@ -0,0 +1 @@
+print(b"\u{0}".format("0394"))  # [anomalous-unicode-escape-in-string]

doc/data/messages/a/anomalous-unicode-escape-in-string/good.py

@@ -0,0 +1 @@
+print(b"\\u{0}".format("0394"))

doc/test_messages_documentation.py

@@ -109,6 +109,7 @@ def _runTest(self) -> None:
 
 
 @pytest.mark.parametrize("test_file", TESTS, ids=TESTS_NAMES)
+@pytest.mark.filterwarnings("ignore::DeprecationWarning")
 def test_code_examples(test_file: Tuple[str, Path]) -> None:
     lint_test = LintModuleTest(test_file)
     lint_test.runTest()