implement aspen qubits and devices

[erichulburd]

This is a draft for supporting very basic topological validation for Rigetti Aspen and Octagonal qubits.

TODO:

• Clean up docstrings in aspen_device.py

[dstrain115]

What is this class for? Generally, classes named utils are a bad code smell, since they attract a lot of miscellaneous unrelated functionality. If this is for testing, can we at least call it test_utils?

[erichulburd]

I added a doc string explaining the function and renamed this file to something more specific about the decorator function.

Normally, we would provide a default kwarg value right within the function signature. The issue here is that we need to initialize the default value as a context value: with build_sync_client() as client:. For that purpose, we use the decorator function.

[balopat]

Thank you - this looks mostly done, I added a couple of nits, please address those and then we can merge - I would love to merge it today / tomorrow morning so that we can add it in the release of v0.12 (Wed / Thu).

[CirqBot]

Automerge cancelled: A required status check is not present.

Missing statuses: ['Build docs', 'Build protos', 'Coverage check', 'Doc test', 'Lint check', 'Notebook formatting', 'Pytest MacOS (3.7)', 'Pytest MacOS (3.8)', 'Pytest MacOS (3.9)', 'Pytest Ubuntu (3.7)', 'Pytest Ubuntu (3.8)', 'Pytest Ubuntu (3.9)', 'Pytest Windows (3.7)', 'Pytest Windows (3.8)', 'Pytest Windows (3.9)', 'Typescript lint check', 'Typescript tests', 'Typescript tests coverage']