Previosuly, we only killed the buildkitd process and unmounted
if builderInfo was non null. This was wrong cause we could have setup
builkdkitd, but failed after that step. This would then rely on the last
ditch effort by the post action to cleanup. We now change the proc kill
and unmount to happen on any build error.
We are incorrectly using formData in a get request. To move
away from this we send both query params and formData until
the server is fully upgraded. After which we can stop sending
formData.
Additionally, write some tests to ensure the driver method
`startBlacksmithBuilder` handles all exceptions correctly in
both nofallback=true and nofallback=false configurations.
Aditya Maru
Aayush