Add flag for getting last submitted task

[lbeckman314]

Overview

Potential minor QoL update for getting info on the last submitted task.

Current Method

Currently the method for getting info on the most recently submitted task is to copy and paste the task id into funnel task get <Task ID>:

➜ funnel task create examples/hello-world.json
# cmsnsf5s99bjdn7svfc0
➜ funnel task get cmsnsf5s99bjdn7svfc0
# <Task Info>

Proposed Method

This could potentially be improved by adding a --last flag to funnel task get that would automatically find and retrieve the most recent task:

➜ funnel task create examples/hello-world.json
# cmsnsf5s99bjdn7svfc0
➜ funnel task get --last
# <Task Info>