[v10.1.x] Azure: Settings for Azure AD Workload Identity (#75683)

* Azure: Settings for Azure AD Workload Identity (#75283)

* Settings for Azure AD Workload Identity

* Update dependency on Grafana Azure SDK

* Documentation

* Fix JS code

* Cleanup Prometheus backend code

* Making prettier happy

(cherry picked from commit 3ee40d3a5a)

# Conflicts:
#	go.mod
#	go.sum
#	public/app/plugins/datasource/mssql/azureauth/AzureAuth.testMocks.ts

* Fix go.sum

---------

Co-authored-by: Sergey Kostrukov <sekost@microsoft.com>

pkg/setting/setting_azure.go

@@ -17,6 +17,24 @@ func (cfg *Cfg) readAzureSettings() {
 	azureSettings.ManagedIdentityEnabled = azureSection.Key("managed_identity_enabled").MustBool(false)
 	azureSettings.ManagedIdentityClientId = azureSection.Key("managed_identity_client_id").String()
 
+	// Workload Identity authentication
+	if azureSection.Key("workload_identity_enabled").MustBool(false) {
+		azureSettings.WorkloadIdentityEnabled = true
+		workloadIdentitySettings := &azsettings.WorkloadIdentitySettings{}
+
+		if val := azureSection.Key("workload_identity_tenant_id").String(); val != "" {
+			workloadIdentitySettings.TenantId = val
+		}
+		if val := azureSection.Key("workload_identity_client_id").String(); val != "" {
+			workloadIdentitySettings.ClientId = val
+		}
+		if val := azureSection.Key("workload_identity_token_file").String(); val != "" {
+			workloadIdentitySettings.TokenFile = val
+		}
+
+		azureSettings.WorkloadIdentitySettings = workloadIdentitySettings
+	}
+
 	// User Identity authentication
 	if azureSection.Key("user_identity_enabled").MustBool(false) {
 		azureSettings.UserIdentityEnabled = true