[ruff] Enable FURB rules for code modernization (#9896)

esphome/cpp_generator.py

@@ -771,8 +771,7 @@ class MockObj(Expression):
         if attr.startswith("P") and self.op not in ["::", ""]:
             attr = attr[1:]
             next_op = "->"
-        if attr.startswith("_"):
-            attr = attr[1:]
+        attr = attr.removeprefix("_")
         return MockObj(f"{self.base}{self.op}{attr}", next_op)
 
     def __call__(self, *args: SafeExpType) -> "MockObj":