How to invoke Slack Web Hook via Grafana

Hello All,

I have a requirement to integrate a Grafana alert rule with a Slack WebHook. The hook has been defined as follows:
The request to the webhook should be POST with the following body
“tenantId”: “Example text”,
“customerName”: “Example text”
Is there a way we can integrate this from Slack. My specific questions is how can I map some text to the tenantId and customerName fields, and execute a POST request.