Re-add tests for Accept Merge Request button.

features/project/merge_requests.feature

@@ -335,6 +335,7 @@ Feature: Project Merge Requests
     And I visit project "Shop" merge requests page
     And merge request 'Bug NS-04' must be approved
     And I click link "Bug NS-04"
+    And I should see the merge button disabled
     When I click link "Approve"
     Then I should see approved merge request "Bug NS-04"
 
@@ -342,6 +343,7 @@ Feature: Project Merge Requests
   Scenario: I can not approve merge request if I am not an approver
     Given merge request 'Bug NS-04' must be approved by some user
     And I click link "Bug NS-04"
+    And I should see the merge button disabled
     When I should not see Approve button
     And I should see message that MR require an approval
 

features/steps/project/merge_requests.rb

@@ -609,6 +609,12 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
     end
   end
 
+  step 'I should see the merge button disabled' do
+    page.within '.mr-state-widget' do
+      expect(page).to have_button('Accept Merge Request', disabled: true)
+    end
+  end
+
   step 'I should not see merge button' do
     page.within '.mr-state-widget' do
       expect(page).not_to have_button('Accept Merge Request')