Unreasonable error message from runner (in Kubernetes)

I got

ERROR: Job failed (system failure): prepare environment: setting up 
build pod: pods "runner-yxuphrz--project-27489025-concurrent-0c6fnr" 
is forbidden: exceeded quota: default-xv9r4, requested: 
limits.cpu=1000250m, used: limits.cpu=500m, limited: limits.cpu=8. 

from my runner on a local cluster. Please note the “1000250m”. Where does this come from? The ci.yaml file is

Slim Build:
  image: debian
    - build
    - sleep 10m