Gemfile: pin request_store version 1.0.5 (#16685)

Many integration tests are broken.

git-svn-id: http://svn.redmine.org/redmine/trunk@13181 e93f8b46-1217-0410-a6f0-8f06a7374b81

Gemfile

@@ -6,7 +6,7 @@ gem "jquery-rails", "~> 2.0.2"
 gem "coderay", "~> 1.1.0"
 gem "fastercsv", "~> 1.5.0", :platforms => [:mri_18, :mingw_18, :jruby]
 gem "builder", "3.0.0"
-gem "request_store"
+gem "request_store", "1.0.5"
 gem "mime-types"
 
 # Optional gem for LDAP authentication