DEV: Add :sidekiq_job_error DiscourseEvent (#32307)

This commit adds a `:sidekiq_job_error` event which is
triggered when an error is encountered while running a Sidekiq job. The
intent of this change is to complement the `:sidekq_job_ran` event which
can be used with the `:sidekiq_job_error` event to calculate the error
rate for each job.

lib/sidekiq/discourse_event.rb

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+class Sidekiq::DiscourseEvent
+  def call(worker, msg, queue)
+    start_time = clock_gettime
+    result = yield
+    trigger_discourse_event(event_name: :sidekiq_job_ran, worker:, msg:, queue:, start_time:)
+    result
+  rescue => error
+    trigger_discourse_event(event_name: :sidekiq_job_error, worker:, msg:, queue:, start_time:)
+    raise error
+  end
+
+  private
+
+  def trigger_discourse_event(event_name:, worker:, msg:, queue:, start_time:)
+    duration = clock_gettime - start_time
+    DiscourseEvent.trigger(event_name, worker, msg, queue, duration)
+  end
+
+  def clock_gettime
+    Process.clock_gettime(Process::CLOCK_MONOTONIC)
+  end
+end