Gracefully handle query timeouts for project VSA

What does this MR do?

Ensures we gracefully handle BE query request timeouts when fetching stage data for project level value streams. When there is too much data to process, the API will raise a timeout, the api request will succeed but an error message is added to the response payload.

This MR checks for the error response and displays it to the user if it is available. This will usually be a message about there being too much data to display.

NOTE: this is mostly because we don't have pagination for the stage table, that will be available once we replace this table with the group level value stream table in #326704 (closed)

Testing instructions

1. Navigate to a project value stream, ie https://gitlab.com/gitlab-org/gitlab/-/value_stream_analytics
2. Click between stages, you will either see data (if you have seeded some) or an empty stage saying 'Not enough data'
3. Apply this patch:

diff --git a/app/controllers/projects/cycle_analytics/events_controller.rb b/app/controllers/projects/cycle_analytics/events_controller.rb
index 3a5dd23047c..09c7cc1349f 100644
--- a/app/controllers/projects/cycle_analytics/events_controller.rb
+++ b/app/controllers/projects/cycle_analytics/events_controller.rb
@@ -14,28 +14,39 @@ class EventsController < Projects::ApplicationController
       feature_category :planning_analytics
 
       def issue
+        raise ActiveRecord::QueryCanceled
+
         render_events(cycle_analytics[:issue].events)
       end
 
       def plan
+        raise ActiveRecord::QueryCanceled
+
         render_events(cycle_analytics[:plan].events)
       end
 
       def code
+        raise ActiveRecord::QueryCanceled
+
         render_events(cycle_analytics[:code].events)
       end
 
       def test
+        raise ActiveRecord::QueryCanceled
         options(cycle_analytics_project_params)[:branch] = cycle_analytics_project_params[:branch_name]
 
         render_events(cycle_analytics[:test].events)
       end
 
       def review
+        raise ActiveRecord::QueryCanceled
+        
         render_events(cycle_analytics[:review].events)
       end
 
       def staging
+        raise ActiveRecord::QueryCanceled
+
         render_events(cycle_analytics[:staging].events)
       end
 

1. Refresh your project value stream, the Too much data error should be shown

Screenshots (strongly suggested)

Before	After

Does this MR meet the acceptance criteria?

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