fix: Fix crash when trying to get a decorator callable path (found th…

…anks to pysource-codegen)

src/griffe/expressions.py

@@ -628,7 +628,7 @@ def iterate(self, *, flat: bool = True) -> Iterator[str | Expr]:  # noqa: D102
 class ExprSubscript(Expr):
     """Subscripts like `a[b]`."""
 
-    left: Expr
+    left: str | Expr
     """Left part."""
     slice: Expr  # noqa: A003
     """Slice part."""
@@ -642,11 +642,15 @@ def iterate(self, *, flat: bool = True) -> Iterator[str | Expr]:  # noqa: D102
     @property
     def path(self) -> str:
         """The path of this subscript's left part."""
+        if isinstance(self.left, str):
+            return self.left
         return self.left.path
 
     @property
     def canonical_path(self) -> str:
         """The canonical path of this subscript's left part."""
+        if isinstance(self.left, str):
+            return self.left
         return self.left.canonical_path