Add delayed response message for holidays (#597)

* Add delayed response message for holidays

* Remove the table from the markdown

Author: lahirumaramba

.github/ISSUE_TEMPLATE/bug_report.md

@@ -7,6 +7,8 @@ assignees: ''
 
 ---
 
+**Thank you for submitting your issue. We are operating at reduced capacity from Dec 17 2021 to Jan 4 2022. Please expect delayed responses. For more urgent requests please reach us via our support channels https://firebase.google.com/support**
+
 ### [READ] Step 1: Are you in the right place?
 
   * For issues related to __the code in this repository__ file a GitHub issue.