.travis.yml in mini_racer-0.4.0 vs .travis.yml in mini_racer-0.5.0.pre

@@ -1,31 +1,23 @@
 language: ruby
 os: linux
 rvm:
-  - 2.4
-  - 2.5
   - 2.6
   - 2.7
   - 3.0
   - ruby-head
 arch:
   - amd64
   - arm64
 jobs:
   include:
-    - rvm: 2.5
-      os: osx
-      osx_image: xcode9.4
     - rvm: 2.6
       os: osx
       osx_image: xcode11.3
     - rvm: 2.6
       os: osx
       osx_image: xcode12.2
     - rvm: 2.7
       os: osx
       osx_image: xcode12.2
 dist: xenial
-before_install:
-  - gem update --system
-  - gem install bundler -v 1.16.2
 cache: bundler