Backport PR #55082 on branch 2.1.x (Updated future warning msg in tra…

…nsform() for Series.groupby) (#55097)

Backport PR #55082: Updated future warning msg in transform() for Series.groupby

Co-authored-by: Rajat Subhra Mukherjee <raromukherjee@gmail.com>

pandas/core/apply.py

@@ -1830,12 +1830,12 @@ def warn_alias_replacement(
         full_alias = alias
     else:
         full_alias = f"{type(obj).__name__}.{alias}"
-        alias = f"'{alias}'"
+        alias = f'"{alias}"'
     warnings.warn(
         f"The provided callable {func} is currently using "
         f"{full_alias}. In a future version of pandas, "
         f"the provided callable will be used directly. To keep current "
-        f"behavior pass {alias} instead.",
+        f"behavior pass the string {alias} instead.",
         category=FutureWarning,
         stacklevel=find_stack_level(),
     )