Some teams utilize bots to assist with merging PRs. Bot activity can be excluded from your metrics via your Contributors Settings.
How excuse bots:
Head to your Contributors Settings
Filter by "Visible Contributors"
Search for and select one or more bots you'd like to exclude
4. Click the eyeball icon to Hide in reports.
Alternatively, you can hide a bot from reports via the bot's profile on the User Settings page:
Click on the bot you'd like to exclude
Uncheck the "Included in reports" box
Click Update contributor