Remove `fancy_pipeline_slack_notifications` flag

This commit removes the `fancy_pipeline_slack_notifications` feature
flag and associated code paths and tests.

app/models/project_services/chat_message/pipeline_message.rb

@@ -52,8 +52,6 @@ module ChatMessage
     def attachments
       return message if markdown
 
-      return [{ text: format(message), color: attachment_color }] unless fancy_notifications?
-
       [{
         fallback: format(message),
         color: attachment_color,
@@ -103,10 +101,6 @@ module ChatMessage
       failed_jobs.uniq { |job| job[:name] }.reverse
     end
 
-    def fancy_notifications?
-      Feature.enabled?(:fancy_pipeline_slack_notifications, default_enabled: true)
-    end
-
     def failed_stages_field
       {
         title: s_("ChatMessage|Failed stage").pluralize(failed_stages.length),
@@ -166,42 +160,22 @@ module ChatMessage
     end
 
     def humanized_status
-      if fancy_notifications?
-        case status
-        when 'success'
-          detailed_status == "passed with warnings" ? s_("ChatMessage|has passed with warnings") : s_("ChatMessage|has passed")
-        when 'failed'
-          s_("ChatMessage|has failed")
-        else
-          status
-        end
+      case status
+      when 'success'
+        detailed_status == "passed with warnings" ? s_("ChatMessage|has passed with warnings") : s_("ChatMessage|has passed")
+      when 'failed'
+        s_("ChatMessage|has failed")
       else
-        case status
-        when 'success'
-          s_("ChatMessage|passed")
-        when 'failed'
-          s_("ChatMessage|failed")
-        else
-          status
-        end
+        status
       end
     end
 
     def attachment_color
-      if fancy_notifications?
-        case status
-        when 'success'
-          detailed_status == 'passed with warnings' ? 'warning' : 'good'
-        else
-          'danger'
-        end
+      case status
+      when 'success'
+        detailed_status == 'passed with warnings' ? 'warning' : 'good'
       else
-        case status
-        when 'success'
-          'good'
-        else
-          'danger'
-        end
+        'danger'
       end
     end
 
@@ -230,7 +204,7 @@ module ChatMessage
     end
 
     def pipeline_url
-      if fancy_notifications? && failed_jobs.any?
+      if failed_jobs.any?
         pipeline_failed_jobs_url
       else
         "#{project_url}/pipelines/#{pipeline_id}"

locale/gitlab.pot

@@ -3633,9 +3633,6 @@ msgstr ""
 msgid "ChatMessage|and [%{count} more](%{pipeline_failed_jobs_url})"
 msgstr ""
 
-msgid "ChatMessage|failed"
-msgstr ""
-
 msgid "ChatMessage|has failed"
 msgstr ""
 
@@ -3651,9 +3648,6 @@ msgstr ""
 msgid "ChatMessage|in %{project_link}"
 msgstr ""
 
-msgid "ChatMessage|passed"
-msgstr ""
-
 msgid "Check again"
 msgstr ""