Improve explore projects spinach test

Project name "Internal" is too generic and can lead to false
positive/negative when there is a visibility filter on the page. So we
ensure we check for project inside list holder css class.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

features/steps/shared/project.rb

@@ -166,11 +166,15 @@ module SharedProject
   end
   step 'I should see project "Internal"' do
-    expect(page).to have_content "Internal"
+    page.within '.js-projects-list-holder' do
+      expect(page).to have_content "Internal"
+    end
   end
   step 'I should not see project "Internal"' do
-    expect(page).not_to have_content "Internal"
+    page.within '.js-projects-list-holder' do
+      expect(page).not_to have_content "Internal"
+    end
   end
   step 'public project "Community"' do