Wmt priority execution feature (#1546)

* Execute the queries with high/low priority

* improvement made to the Cosmos client and created separate plugin class for setting priority header

* added test cases for the priority execution utility

* removed unwanted code

* fix compile time issues

* fix compile time issues

* fixed lint and stylinkg issues

* fixed lint and styling issues

* skip the lint check for src/Utils/PriorityBasedExecutionUtils.ts

* incorporating review comments, added the default priority level changes

* changed the priority to default instead of low

* removed the unwanted if condition

---------

Co-authored-by: Faiz Chachiya <faizchachiya@microsoft.com>

src/Shared/ExplorerSettings.ts

@@ -6,6 +6,7 @@ export const createDefaultSettings = () => {
   LocalStorageUtility.setEntryNumber(StorageKey.CustomItemPerPage, Constants.Queries.itemsPerPage);
   LocalStorageUtility.setEntryString(StorageKey.IsCrossPartitionQueryEnabled, "true");
   LocalStorageUtility.setEntryNumber(StorageKey.MaxDegreeOfParellism, Constants.Queries.DefaultMaxDegreeOfParallelism);
+  LocalStorageUtility.setEntryString(StorageKey.PriorityLevel, Constants.PriorityLevel.Default);
 };
 
 export const hasSettingsDefined = (): boolean => {
@@ -15,3 +16,9 @@ export const hasSettingsDefined = (): boolean => {
     LocalStorageUtility.hasItem(StorageKey.MaxDegreeOfParellism)
   );
 };
+
+export const ensurePriorityLevel = () => {
+  if (!LocalStorageUtility.hasItem(StorageKey.PriorityLevel)) {
+    LocalStorageUtility.setEntryString(StorageKey.PriorityLevel, Constants.PriorityLevel.Default);
+  }
+};

src/Shared/StorageUtility.ts

@@ -16,4 +16,5 @@ export enum StorageKey {
   SetPartitionKeyUndefined,
   GalleryCalloutDismissed,
   VisitedAccounts,
+  PriorityLevel,
 }