Remove bad links to qiskit.org

[Eric-Arellano]

qiskit.org is being sunset, per https://medium.com/qiskit/important-changes-to-qiskit-documentation-and-learning-resources-7f4e346b19ab. So, we should stop linking to qiskit.org in the API docs.

Problem	Bad link	Redirect
qiskit_ibm_runtime/qiskit_runtime_service.py 565	https://qiskit.org/documentation/apidoc/providers_models.html	https://docs.quantum-computing.ibm.com/api/qiskit/providers
qiskit_ibm_runtime/session.py 91	https://qiskit.org/documentation/partners/qiskit_ibm_runtime/faqs/max_execution_time.html	https://docs.quantum-computing.ibm.com/run/max-execution-time
qiskit_ibm_runtime/options/options.py 61	https://qiskit.org/documentation/partners/qiskit_ibm_runtime	https://docs.quantum-computing.ibm.com/run/configure-error-mitigation