bluoes_startup_update: add fine-grained patch suppression

[Williangalvani]

tested by running BLUEOS_DISABLE_PATCHES=userdata,cgroups,nginx,dwc2,ssh,i2c4,dns blueos_startup_update.py

fix #3035

[drzwey]

Great, thanks! I'll check it out.

[ES-Alexander]

Would be good to mention this functionality in the dev docs :-)

---

• Should add a section for running BlueOS with environment variables, using startup.json

  {
    "core": {
      "binds": {
         ....
      },
      "enabled": true,
      "environment": [
        "BLUEOS_DISABLE_SERVICES='ping'"
      ],
      "image": "bluerobotics/blueos-core",
      "network": "host",
      "privileged": true,
      "tag": "master"
    }
  }
  

• Should list the available variables
  • BLUEOS_DISABLE_SERVICES
  • BLUEOS_DISABLE_PATCHES
  • BLUEOS_DISABLE_STARTUP_UPDATE
  • BLUEOS_DISABLE_MEMORY_LIMIT