pr-fix: use correct var name

src/Arcus.Observability.Tests.Integration/Serilog/Sinks/ApplicationInsights/AppInsightsClient.cs

@@ -28,7 +28,7 @@ public AppInsightsClient(TestConfig config)
         {
             ServicePrincipal servicePrincipal = config.GetServicePrincipal();
             _queryClient = new LogsQueryClient(new ClientSecretCredential(servicePrincipal.TenantId, servicePrincipal.ClientId, servicePrincipal.ClientSecret));
-            _resourceId = config["Arcus:LogAnalyticsWorkspace:ResourceId"];
+            _resourceId = config["Arcus:ApplicationInsights:LogAnalyticsWorkspace:ResourceId"];
             _timeRange = new QueryTimeRange(TimeSpan.FromDays(1));
         }