Fix: Preserve dict insertion order in assertion output

Remove sorted() calls in PrettyPrinter to preserve dict insertion order.

Since Python 3.7+, dicts maintain insertion order. Sorting keys
alphabetically in assertion failures is confusing and doesn't match
how Python naturally displays dicts.

Changes:
- _pprint_dict: Remove sorted() on object.items()
- _safe_repr: Remove sorted() on dict.items() iteration

Fixes #13503

Author: hrideymarwah15

src/_pytest/_io/pprint.py

@@ -162,7 +162,7 @@ def _pprint_dict(
     ) -> None:
         write = stream.write
         write("{")
-        items = sorted(object.items(), key=_safe_tuple)
+        items = object.items()
         self._format_dict_items(items, stream, indent, allowance, context, level)
         write("}")
 
@@ -608,7 +608,7 @@ def _safe_repr(
             components: list[str] = []
             append = components.append
             level += 1
-            for k, v in sorted(object.items(), key=_safe_tuple):
+            for k, v in object.items():
                 krepr = self._safe_repr(k, context, maxlevels, level)
                 vrepr = self._safe_repr(v, context, maxlevels, level)
                 append(f"{krepr}: {vrepr}")