Add ability to set CPU and Memory for scheduled task

[davidsiaw]

Previously it was not possible to set a scheduled task's Memory or CPU usage, and it was pinned at 512MB of RAM and 128 units of CPU. This needs to change as some tasks require more memory.

[degicat]

@Iorin0225 please review this

[davidsiaw]

@Iorin0225 sorry I meant to put @k2nr on this review but I think I messed up the command. I will remove you as reviewer for this PR

[k2nr]

I think it's better to set cpu and memory per task like this. Also, same as services, can we change cpu default to nil?

scheduled_tasks:
  - schedule: rate(5 minutes)
    command: some_task
    memory: 1024
  - ...

[davidsiaw]

I think it's better to set cpu and memory per task like this

This is a little more complicated to do because we store this information per heritage. This will involve changing the model and moving a bunch of things around. For now the idea is just to make it modifiable.

can we change cpu default to nil?

We can, I just kept the CPU the same so we don't change too many things at once. I can put up a PR that sets the scheduled task CPU to default to nil. I can't think of any possible problems with that, but there could be problems that would emerge that I don't know.