You weren't clear on if your web app is running on PaaS or IaaS; but you can leverage Azure Automation to run a PowerShell runbook execute the appropriate Az module to restart your web app. For instance, if you needed to restart your app service, the runbook would contain something like
# Stop the App Service
Stop-AzWebApp -ResourceGroupName "myresourcegroup" -Name "myappservice"
# Start the App Service
Start-AzWebApp -ResourceGroupName "myresourcegroup" -Name "myappservice"