Another self-compilation fix

Author: Ivan Levkivskyi

mypy/checker_shared.py

@@ -135,12 +135,16 @@ def infer_literal_expr_type(self, value: LiteralValue, fallback_name: str) -> Ty
 
 @trait
 class TypeCheckerSharedApi(CheckerPluginInterface):
-    expr_checker: ExpressionCheckerSharedApi
     plugin: Plugin
     module_refs: set[str]
     scope: CheckerScope
     checking_missing_await: bool
 
+    @property
+    @abstractmethod
+    def expr_checker(self) -> ExpressionCheckerSharedApi:
+        raise NotImplementedError
+
     @abstractmethod
     def named_type(self, name: str) -> Instance:
         raise NotImplementedError