Update bot code for Drupal 11 and PHP 8.1. Fixed some misc code style as I went along.

Closes #3413931

issues_bot/.ddev/config.yaml

 name: issue-bot
 type: php
 docroot: ""
-php_version: "7.4"
+php_version: "8.1"
 webserver_type: nginx-fpm
 router_http_port: "80"
 router_https_port: "443"
@@ -17,6 +17,7 @@ use_dns_when_possible: true
 composer_version: "2"
 web_environment: []
 nodejs_version: "16"
+webimage_extra_packages: ['patchutils']
 
 # Key features of ddev's config.yaml: