fix: use environment variable for ACME schedule configuration

src/function/index.ts

@@ -3,7 +3,7 @@ import { loadConfig } from '../lib/config.js';
 import { Provisioner } from '../lib/provisioner.js';
 
 app.timer('acmeProvisioner', {
-  schedule: '0 0 2 * * *',
+  schedule: process.env['ACME_SCHEDULE'] ?? '0 0 2 * * *',
   useMonitor: true,
   handler: async (_timer: Timer, context: InvocationContext): Promise<void> => {
     context.log('Azure ACME Provisioner starting');