Add Travis badge image to `README.md`. [ci skip] (#4527)

Align the order of the badges with ones on the wiki page.
https://bugs.ruby-lang.org/projects/ruby/wiki/CIServers

README.md

@@ -1,9 +1,10 @@
-[![Build status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/master?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/master)
 [![Actions Status: macOS](https://github.com/ruby/ruby/workflows/macOS/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"macOS")
 [![Actions Status: MinGW](https://github.com/ruby/ruby/workflows/MinGW/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MinGW")
 [![Actions Status: MJIT](https://github.com/ruby/ruby/workflows/MJIT/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MJIT")
 [![Actions Status: Ubuntu](https://github.com/ruby/ruby/workflows/Ubuntu/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Ubuntu")
 [![Actions Status: Windows](https://github.com/ruby/ruby/workflows/Windows/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Windows")
+[![AppVeyor status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/master?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/master)
+[![Travis Status](https://www.travis-ci.com/ruby/ruby.svg?branch=master)](https://www.travis-ci.com/ruby/ruby)
 
 # What's Ruby