Revert "Lock boostrap-sass to 2.3.0.1 until this issue is fixed - twb…

…s/bootstrap#7118"

Reverting because this causes another issue: twbs/bootstrap#6835
Fixes https://squish.ish.com.au/tasks/view/17768

This reverts commit 73e8523.

Gemfile

@@ -50,8 +50,7 @@ end
 # in production environments by default.
 group :assets do
   gem 'sass-rails'
-  # Lock to 2.3.0.1 until this issue is fixed - https://github.com/twitter/bootstrap/issues/7118
-  gem 'bootstrap-sass', '2.3.0.1'
+  gem 'bootstrap-sass'
 end
 
 group :test, :development do

Gemfile.lock

@@ -50,7 +50,7 @@ GEM
     arel (3.0.2)
     bcrypt-ruby (3.0.1)
     bcrypt-ruby (3.0.1-java)
-    bootstrap-sass (2.3.0.1)
+    bootstrap-sass (2.3.1.0)
       sass (~> 3.2)
     bourne (1.4.0)
       mocha (~> 0.13.2)
@@ -255,7 +255,7 @@ DEPENDENCIES
   acts_as_list
   acts_as_tree
   annotate
-  bootstrap-sass (= 2.3.0.1)
+  bootstrap-sass
   capybara
   ci_reporter
   closure-compiler