Remove IQP classic integration tests

[kt474]

Summary

On 6/2 all backends will be removed from internal hubs in IQP classic so our integration tests will no longer be able to run.

Details and comments

Fixes #2257

[ElePT]

I am not sure if this is due to my environment, but when testing the integration tests locally I see quite a lot of failures that look like:

======================================================================
ERROR: setUpClass (test.integration.test_sampler_v2.TestSampler)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/ept/qiskit_workspace/qiskit-ibm-runtime/test/decorators.py", line 105, in _wrapper
    channel, token, url, instance, qpu = _get_integration_test_config()
                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/ept/qiskit_workspace/qiskit-ibm-runtime/test/decorators.py", line 64, in _get_integration_test_config
    channel: str = "ibm_cloud" if url.find("cloud") >= 0 else "ibm_quantum"
                                  ^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'find'

======================================================================
ERROR: setUpClass (test.integration.test_session.TestIntegrationSession)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/ept/qiskit_workspace/qiskit-ibm-runtime/test/decorators.py", line 105, in _wrapper
    channel, token, url, instance, qpu = _get_integration_test_config()
                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/ept/qiskit_workspace/qiskit-ibm-runtime/test/decorators.py", line 64, in _get_integration_test_config
    channel: str = "ibm_cloud" if url.find("cloud") >= 0 else "ibm_quantum"
                                  ^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'find'

I know that these are not introduced by this PR, but they might be masking other failures.

[kt474]

I know that these are not introduced by this PR, but they might be masking other failures.

Those errors are because the credentials have not been set. I can show you how to run the tests locally