[deprecation] 'check_single_file' replaced by 'check_single_file_item'

Author: Pierre-Sassoulas

doc/whatsnew/fragments/8478.internal

@@ -0,0 +1,4 @@
+Following a deprecation period, the ``check_single_file`` function of the
+``Pylinter`` is replaced by ``Pylinter.check_single_file_item``.
+
+Refs #8478

pylint/lint/pylinter.py

@@ -12,7 +12,6 @@
 import sys
 import tokenize
 import traceback
-import warnings
 from collections import defaultdict
 from collections.abc import Callable, Iterator, Sequence
 from io import TextIOWrapper
@@ -714,15 +713,6 @@ def _get_asts(
 
         return ast_per_fileitem
 
-    def check_single_file(self, name: str, filepath: str, modname: str) -> None:
-        warnings.warn(
-            "In pylint 3.0, the checkers check_single_file function will be removed. "
-            "Use check_single_file_item instead.",
-            DeprecationWarning,
-            stacklevel=2,
-        )
-        self.check_single_file_item(FileItem(name, filepath, modname))
-
     def check_single_file_item(self, file: FileItem) -> None:
         """Check single file item.