Merge branch 'fix-merge-request-diff-spinach-failures' into 'master'

Fix Spinach merge request diff failures

gitlab-git-test `master` was updated in ff076d88, and this caused the merge request diffs to change in a way that broke assumptions in the Spinach tests.
    
Partial fix to #23378

See merge request !6916

features/steps/project/merge_requests.rb

@@ -7,6 +7,7 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
   include SharedMarkdown
   include SharedDiffNote
   include SharedUser
+  include WaitForAjax
 
   step 'I click link "New Merge Request"' do
     click_link "New Merge Request"
@@ -90,6 +91,7 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
 
   step 'I click button "Unsubscribe"' do
     click_on "Unsubscribe"
+    wait_for_ajax
   end
 
   step 'I click link "Close"' do
@@ -114,7 +116,7 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
            source_project: project,
            target_project: project,
            source_branch: 'fix',
-           target_branch: 'master',
+           target_branch: 'merge-test',
            author: project.users.first,
            description: "# Description header"
           )
@@ -137,7 +139,8 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
            title: "Bug NS-05",
            source_project: project,
            target_project: project,
-           author: project.users.first)
+           author: project.users.first,
+           source_branch: 'merge-test')
   end
 
   step 'project "Shop" have "Feature NS-05" merged merge request' do
@@ -508,7 +511,7 @@ class Spinach::Features::ProjectMergeRequests < Spinach::FeatureSteps
 
   step 'I should see new target branch changes' do
     expect(page).to have_content 'Request to merge fix into feature'
-    expect(page).to have_content 'Target branch changed from master to feature'
+    expect(page).to have_content 'Target branch changed from merge-test to feature'
   end
 
   step 'I click on "Email Patches"' do

features/steps/shared/note.rb

+require Rails.root.join('features/support/wait_for_ajax')
+
 module SharedNote
   include Spinach::DSL
+  include WaitForAjax
 
   step 'I delete a comment' do
     page.within('.main-notes-list') do
@@ -116,8 +119,9 @@ module SharedNote
     page.within(".js-main-target-form") do
       fill_in "note[note]", with: "# Comment with a header"
       click_button "Comment"
-      sleep 0.05
     end
+
+    wait_for_ajax
   end
 
   step 'The comment with the header should not have an ID' do

spec/support/test_env.rb

@@ -17,6 +17,7 @@ module TestEnv
     'markdown'                           => '0ed8c6c',
     'lfs'                                => 'be93687',
     'master'                             => 'b83d6e3',
+    'merge-test'                         => '5937ac0',
     "'test'"                             => 'e56497b',
     'orphaned-branch'                    => '45127a9',
     'binary-encoding'                    => '7b1cf43',