Fix hit miss of Show all activity button

ee/app/assets/javascripts/related_issues/components/related_issues_block.vue

@@ -214,7 +214,7 @@ export default {
         }"
         class="related-issues-token-body"
       >
-        <div v-if="isFetching" class="related-issues-loading-icon">
+        <div v-if="isFetching" class="related-issues-loading-icon qa-related-issues-loading-icon">
           <gl-loading-icon
             ref="loadingIcon"
             label="Fetching related issues"

qa/qa/ee.rb

@@ -56,6 +56,7 @@ module QA
 
         module Issue
           autoload :Index, 'qa/ee/page/project/issue/index'
+          autoload :Show, 'qa/ee/page/project/issue/show'
         end
 
         module Settings

qa/qa/ee/page/project/issue/show.rb

+# frozen_string_literal: true
+
+module QA
+  module EE
+    module Page
+      module Project
+        module Issue
+          module Show
+            def self.prepended(page)
+              page.module_eval do
+                view 'ee/app/assets/javascripts/related_issues/components/related_issues_block.vue' do
+                  element :related_issues_loading_icon
+                end
+              end
+            end
+
+            def wait_for_related_issues_to_load
+              wait(reload: false) do
+                has_no_element?(:related_issues_loading_icon)
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+end

qa/qa/page/project/issue/show.rb

@@ -5,6 +5,7 @@ module QA
     module Project
       module Issue
         class Show < Page::Base
+          prepend QA::EE::Page::Project::Issue::Show
           include Page::Component::Issuable::Common
           include Page::Component::Note
 

qa/qa/specs/features/browser_ui/2_plan/ee_epic/create_edit_delete_epic_spec.rb

@@ -49,6 +49,7 @@ module QA
         issue.visit!
 
         Page::Project::Issue::Show.perform do |show_page|
+          show_page.wait_for_related_issues_to_load
           show_page.select_all_activities_filter
           show_page.comment("/epic #{epic.web_url}")
           show_page.comment("/remove_epic")