MNT Update CI badges (scikit-learn#18877)

Author: ogrisel

README.rst

@@ -1,19 +1,22 @@
 .. -*- mode: rst -*-
 
-|Azure|_ |Travis|_ |Codecov|_ |CircleCI|_ |PythonVersion|_ |PyPi|_ |DOI|_
+|Azure|_ |Travis|_ |Codecov|_ |CircleCI|_ |Nightly wheels|_ |PythonVersion|_ |PyPi|_ |DOI|_
 
 .. |Azure| image:: https://dev.azure.com/scikit-learn/scikit-learn/_apis/build/status/scikit-learn.scikit-learn?branchName=master
 .. _Azure: https://dev.azure.com/scikit-learn/scikit-learn/_build/latest?definitionId=1&branchName=master
 
-.. |Travis| image:: https://api.travis-ci.org/scikit-learn/scikit-learn.svg?branch=master
-.. _Travis: https://travis-ci.org/scikit-learn/scikit-learn
+.. |Travis| image:: https://api.travis-ci.com/scikit-learn/scikit-learn.svg?branch=master
+.. _Travis: https://travis-ci.com/scikit-learn/scikit-learn
 
 .. |Codecov| image:: https://codecov.io/github/scikit-learn/scikit-learn/badge.svg?branch=master&service=github
 .. _Codecov: https://codecov.io/github/scikit-learn/scikit-learn?branch=master
 
 .. |CircleCI| image:: https://circleci.com/gh/scikit-learn/scikit-learn/tree/master.svg?style=shield&circle-token=:circle-token
 .. _CircleCI: https://circleci.com/gh/scikit-learn/scikit-learn
 
+.. |Nightly wheels| image:: https://github.com/scikit-learn/scikit-learn/workflows/Wheel%20builder/badge.svg?event=schedule
+.. _`Nightly wheels`: https://github.com/scikit-learn/scikit-learn/actions?query=workflow%3A%22Wheel+builder%22+event%3Aschedule
+
 .. |PythonVersion| image:: https://img.shields.io/badge/python-3.6%20%7C%203.7%20%7C%203.8-blue
 .. _PythonVersion: https://img.shields.io/badge/python-3.6%20%7C%203.7%20%7C%203.8-blue