gh-124889: Remove redundant artificial rules, some refactoring 2 (#124893)

Explicit using of "is_repeat1" kwarg is added to visit_Repeat0 and visit_Repeat1 methods.
Its slightly improve code readabitily.

Author: efimov-mikhail

Tools/peg_generator/pegen/c_generator.py

@@ -324,15 +324,15 @@ def visit_Repeat0(self, node: Repeat0) -> FunctionCall:
         return self._generate_artificial_rule_call(
             node,
             "repeat0",
-            lambda: self.gen.artificial_rule_from_repeat(node.node, False),
+            lambda: self.gen.artificial_rule_from_repeat(node.node, is_repeat1=False),
             "asdl_seq *",
         )
 
     def visit_Repeat1(self, node: Repeat1) -> FunctionCall:
         return self._generate_artificial_rule_call(
             node,
             "repeat1",
-            lambda: self.gen.artificial_rule_from_repeat(node.node, True),
+            lambda: self.gen.artificial_rule_from_repeat(node.node, is_repeat1=True),
             "asdl_seq *",
         )