[fix] Auto email report not working

frappe/email/doctype/auto_email_report/auto_email_report.js

@@ -66,7 +66,9 @@ frappe.ui.form.on('Auto Email Report', {
 
 			var filters = JSON.parse(frm.doc.filters || '{}');
 			var report_filters = frappe.query_reports[frm.doc.report].filters;
-			frm.set_value('filter_meta', JSON.stringify(report_filters));
+			if(report_filters.length > 0) {
+				frm.set_value('filter_meta', JSON.stringify(report_filters));
+			}
 
 			report_filters_list = []
 			$.each(report_filters, function(key, val){