[ci]: Unsync auto-labels. Fix config-changes condition

[s8sato]

Description

Linked issue

1. The bot was observed to remove a label manually added to PR: [feature] #4212: Prevent account registration without signatures #4309 (comment)
2. At the same time, the bot was observed to notify false-positive config-changes due to its wrong definition
   • Closes Automatic notification about config.json changes through CI #4278

Benefits

1. Always prioritize manual labeling/unlabeling
2. Necessary and sufficient config-changes notifications

Checklist

• I've read CONTRIBUTING.md
• I've used the standard signed-off commit format (or will squash just before merging)
• All applicable CI checks pass (or I promised to make them pass later)
• (optional) I've written unit tests for the code changes
• I replied to all comments after code review, marking all implemented changes with thumbs up