Add SQC backend

[rwakizaka]

Summary

Add a SQC backend to integrates qiskit-cpp with SQC (https://github.com/jhpc-quantum/SQC/tree/main).

Details and comments

• Added a new backend for SQC
• Added a new job class for SQC
• Added a new runtime service for SQC
  • Users can change preferable runtime service by switching the include file

[NOTE] Currently SQC C-API seems not to provide async job execution, so this PR lacks of there features:

• Getting a job status
• Async execution of sampler pubs
  • That is, we need to wait the completion of our jobs when calling SQCBackend::run

[rwakizaka]

Thanks to @ohtanim, we confirmed that the sampler test using SQC works as expected.

[rwakizaka]

@doichanj README is updated. Could you check?