Add SQL Managed Instance support and sorting (#7996)

- Add SQL Instances folder and support using existing SQLClient API
- Sort subscriptions in tree and quickpick for easier search
- Sort all resources (Databases, Servers, Instances) alphabetically too

Not in this PR:
- Will experiment with Graph API for faster perf & easier addition of other Azure resources such as PostgreSQL

extensions/azurecore/src/azureResource/tree/accountTreeNode.ts

@@ -80,11 +80,12 @@ export class AzureResourceAccountTreeNode extends AzureResourceContainerTreeNode
 			if (subscriptions.length === 0) {
 				return [AzureResourceMessageTreeNode.create(AzureResourceAccountTreeNode.noSubscriptionsLabel, this)];
 			} else {
-				return await Promise.all(subscriptions.map(async (subscription) => {
+				let subTreeNodes = await Promise.all(subscriptions.map(async (subscription) => {
 					const tenantId = await this._tenantService.getTenantId(subscription);
 
 					return new AzureResourceSubscriptionTreeNode(this.account, subscription, tenantId, this.appContext, this.treeChangeHandler, this);
 				}));
+				return subTreeNodes.sort((a, b) => a.subscription.name.localeCompare(b.subscription.name));
 			}
 		} catch (error) {
 			if (error instanceof AzureResourceCredentialError) {
@@ -163,4 +164,4 @@ export class AzureResourceAccountTreeNode extends AzureResourceContainerTreeNode
 	private _selectedSubscriptionCount = 0;
 
 	private static readonly noSubscriptionsLabel = localize('azure.resource.tree.accountTreeNode.noSubscriptionsLabel', "No Subscriptions found.");
-}
+}

extensions/azurecore/src/azureResource/tree/subscriptionTreeNode.ts

@@ -54,7 +54,7 @@ export class AzureResourceSubscriptionTreeNode extends AzureResourceContainerTre
 					// To make tree node's id unique, otherwise, treeModel.js would complain 'item already registered'
 					child.resourceNode.treeItem.id = `${this._id}.${child.resourceNode.treeItem.id}`;
 					return new AzureResourceResourceTreeNode(child, this, this.appContext);
-				});
+				}).sort((a, b) => a.nodePathValue.localeCompare(b.nodePathValue));
 			}
 		} catch (error) {
 			return [AzureResourceMessageTreeNode.create(AzureResourceErrorMessageUtil.getErrorMessage(error), this)];