Add health checks to the runner

[abetomo]

Describe the feature you want

• Arm
  • Is the CAN bus active?
  • ...
• Camera
  • Is the camera active?
  • ...
• Docker image
  • Does the specified Docker image exist?
  • ...
• Task
  • Is everything ready for evaluate?
  • ...
• dora
  • Has dora been built?
  • ...
• System resource
  • Free disk space
  • ...

Also consider when to run each check (at startup, before running a job, etc.).