builder: return error if all nodes fail to boot

[crazy-max]

fixes docker/setup-buildx-action#228 (comment)

Before:

#1 [internal] booting buildkit
#1 pulling image moby/buildkit:buildx-stable-1
#1 pulling image moby/buildkit:buildx-stable-1 1.6s done
#1 creating container buildx_buildkit_builder-cc8757dc-a94d-4ea0-ac4a-592280318e710 done
#1 ERROR: Error response from daemon: Windows does not support privileged mode
------
 > [internal] booting buildkit:
------
Name:          builder-cc8757dc-a94d-4ea0-ac4a-592280318e71
Driver:        docker-container
Last Activity: 2023-10-23 12:13:15 +0000 UTC

Nodes:
Name:      builder-cc8757dc-a94d-4ea0-ac4a-592280318e710
Endpoint:  npipe:////./pipe/docker_engine
Status:    inactive
Flags:     --allow-insecure-entitlement security.insecure --allow-insecure-entitlement network.host
Platforms:

Now:

#1 [internal] booting buildkit
pedantic_hopper
#1 pulling image moby/buildkit:buildx-stable-1
#1 pulling image moby/buildkit:buildx-stable-1 1.4s done
#1 creating container buildx_buildkit_pedantic_hopper0 0.0s done
#1 ERROR: Error response from daemon: Windows does not support privileged mode
------
 > [internal] booting buildkit:
------
ERROR: Error response from daemon: Windows does not support privileged mode