add whatsnew note, set min version

Author: fangchenli

doc/source/whatsnew/v1.3.0.rst

@@ -88,6 +88,8 @@ If installed, we now require:
 +-----------------+-----------------+----------+---------+
 | mypy (dev)      | 0.782           |          |         |
 +-----------------+-----------------+----------+---------+
+| setuptools      | 38.6.0          |          |    X    |
++-----------------+-----------------+----------+---------+
 
 For `optional libraries <https://dev.pandas.io/docs/install.html#dependencies>`_ the general recommendation is to use the latest version.
 The following table lists the lowest version per library that is currently being tested throughout the development of pandas.

pyproject.toml

@@ -2,7 +2,7 @@
 # Minimum requirements for the build system to execute.
 # See https://github.com/scipy/scipy/pull/12940 for the AIX issue.
 requires = [
-    "setuptools",
+    "setuptools>=38.6.0",
     "wheel",
     "Cython>=0.29.21,<3",  # Note: sync with setup.py
     "numpy==1.16.5; python_version=='3.7'",