[Cloudfunction] Synthetic Monitoring

[anovis]

Add integration for a Synthetic Monitoring cloudfunction. It would create a route for monitoring, create an alert, and pass through various thresholds to the monitoring dashboard.

@app.synthetic_monitor()

https://cloud.google.com/blog/products/management-tools/cloud-monitoring-adds-synthetic-monitoring-feature

[anovis]

Only cloudfunctionv2 is supported.
https://cloud.google.com/monitoring/api/ref_v3/rest/v3/projects.uptimeCheckConfigs#SyntheticMonitorTarget