Add retries to performance_bar_spec E2E test assertion methods

app/assets/javascripts/performance_bar/components/detailed_metric.vue

@@ -59,7 +59,8 @@ export default {
   <div
     v-if="currentRequest.details && metricDetails"
     :id="`peek-view-${metric}`"
-    class="view qa-performance-bar-detailed-metric"
+    class="view"
+    data-qa-selector="detailed_metric_content"
   >
     <button
       :data-target="`#modal-peek-${metric}-details`"

app/assets/javascripts/performance_bar/components/performance_bar_app.vue

@@ -107,7 +107,11 @@ export default {
 </script>
 <template>
   <div id="js-peek" :class="env">
-    <div v-if="currentRequest" class="d-flex container-fluid container-limited qa-performance-bar">
+    <div
+      v-if="currentRequest"
+      class="d-flex container-fluid container-limited"
+      data-qa-selector="performance_bar"
+    >
       <div id="peek-view-host" class="view">
         <span
           v-if="hasHost"

app/assets/javascripts/performance_bar/components/request_selector.vue

@@ -45,13 +45,13 @@ export default {
 };
 </script>
 <template>
-  <div id="peek-request-selector">
+  <div id="peek-request-selector" data-qa-selector="request_dropdown">
     <select v-model="currentRequestId">
       <option
         v-for="request in requests"
         :key="request.id"
         :value="request.id"
-        class="qa-performance-bar-request"
+        data-qa-selector="request_dropdown_option"
       >
         {{ request.truncatedUrl }}
         <span v-if="request.hasWarnings">(!)</span>

qa/qa/page/layout/performance_bar.rb

@@ -9,11 +9,12 @@ module QA
         end
 
         view 'app/assets/javascripts/performance_bar/components/detailed_metric.vue' do
-          element :performance_bar_detailed_metric
+          element :detailed_metric_content
         end
 
         view 'app/assets/javascripts/performance_bar/components/request_selector.vue' do
-          element :performance_bar_request
+          element :request_dropdown_option
+          element :request_dropdown
         end
 
         def has_performance_bar?
@@ -21,13 +22,18 @@ module QA
         end
 
         def has_detailed_metrics?
-          all_elements(:performance_bar_detailed_metric).all? do |metric|
+          retry_until(sleep_interval: 1) do
+            all_elements(:detailed_metric_content).all? do |metric|
               metric.has_text?(%r{\d+})
             end
           end
+        end
 
         def has_request_for?(path)
-          has_element?(:performance_bar_request, text: path)
+          click_element(:request_dropdown)
+          retry_until(sleep_interval: 1) do
+            has_element?(:request_dropdown_option, text: path)
+          end
         end
       end
     end