Revert "Simulate level 10 in issue bot on 1.12.x"

This reverts commit def9f5a.

Author: ondrejmirtes

.github/workflows/issue-bot.yml

@@ -106,9 +106,6 @@ jobs:
           attempt_limit: 5
           attempt_delay: 1000
 
-      - name: "Add level 10 config file"
-        run: "cp issue-bot/config.level10.neon conf/"
-
       - name: "Run PHPStan"
         working-directory: "issue-bot"
         timeout-minutes: 5