Bump version to 2.7.0.rc.2

Author: justin808

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    react-rails (2.7.0.rc.1)
+    react-rails (2.7.0.rc.2)
       babel-transpiler (>= 0.7.0)
       connection_pool
       execjs

lib/react/rails/version.rb

@@ -2,6 +2,6 @@ module React
   module Rails
     # If you change this, make sure to update VERSIONS.md
     # and republish the UJS by updating package.json and `bundle exec rake ujs:publish`
-    VERSION = '2.7.0.rc.1'
+    VERSION = '2.7.0.rc.2'
   end
 end