Remove old mri platform entries from our Gemfile

Since we now only support Ruby 2.2+, we can safely remove the old mri
entries from the Gemfile.

This also allows us not to lock to a specific bundler version, since
:mri_22 was defined only on 1.7.11.

Closes #19611.

1 files changed, 2 insertions, 9 deletions

diff --git a/Gemfile b/Gemfile
index 70b8a74ddf..4d6b17202f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -63,18 +63,11 @@ group :test do
   # FIX: Our test suite isn't ready to run in random order yet
   gem 'minitest', '< 5.3.4'
 
-  platforms :mri_19 do
-    gem 'ruby-prof', '~> 0.11.2'
-  end
-
-  platforms :mri_21, :mri_22 do
+  platforms :mri do
     gem 'stackprof'
+    # gem 'byebug'
   end
 
-  # platforms :mri do
-  #   gem 'byebug'
-  # end
-
   gem 'benchmark-ips'
 end