Switch to undici Agent for HTTPS requests

Replace https.Agent with undici's Agent for handling self-signed certificates.

Author: in-voker

modules/default/calendar/calendarfetcher.js

@@ -1,8 +1,8 @@
-const https = require("node:https");
 const ical = require("node-ical");
 const Log = require("logger");
 const CalendarFetcherUtils = require("./calendarfetcherutils");
 const { getUserAgent } = require("#server_functions");
+const { Agent } = require('undici');
 
 const FIFTEEN_MINUTES = 15 * 60 * 1000;
 const THIRTY_MINUTES = 30 * 60 * 1000;
@@ -74,8 +74,12 @@ class CalendarFetcher {
 		const options = { headers };
 
 		if (this.selfSignedCert) {
-			options.agent = new https.Agent({ rejectUnauthorized: false });
-		}
+    		options.dispatcher = new Agent({
+      			connect: {
+        			rejectUnauthorized: false
+      			}
+    		});
+  		}
 
 		if (this.auth) {
 			if (this.auth.method === "bearer") {