Usage is measured in "seconds" not in "quantum_seconds"

[raulotaolea]

What is the expected feature or enhancement?

Qiskit Runtime usage, or just usage, is defined here or here as:

Usage: Qiskit Runtime used by this job. This usage is the time counted by Qiskit Runtime to process a job, and is determined by the use of internal resources.

but in the API related with estimations, e.g. RuntimeJob.usage_estimation, we are returning quantum_seconds instead of just seconds. All measures related with Qiskit Runtime must be seconds.

Acceptance criteria

Everything related with Qiskit Runtime usage (real or estimated) must be seconds. In a quick search in this repo I found 4 places where we say quantum_seconds instead of just seconds.

[drew-distefano]

@raulotaolea are we still moving forward with using "seconds" and not "quantum_seconds"?

[mberna]

@raulotaolea have you reached a conclusion for this?

[jyu00]

Closing since quantum_seconds was ok again