Breaking: Update dependencies, fix breakage

[Shadow53]

Resolves #38.

Dependabot showed vulnerabilities in a few dependencies, and this updates them and others.

• python minimum version bumped to 3.8 (required by scipy, a transitive of numpy, I think)
• flake8
• numpy
• mypy
• qiskit
• semantic-release (and plugins)
• Others updated by poetry update

These updates cause a few errors:

• A type: ignore comment is no longer needed
• Tests that used a readout register not called ro failed
  • Fixed this by also applying the rename to instructions

The test coverage shows one line as not covered in _qcs_backend.py:181:

def _set_coupling_map_based_on_qc_topology_if_necessary(self) -> None: 
        configuration: QasmBackendConfiguration = self.configuration() 
        if not configuration.coupling_map and self._auto_set_coupling_map: 
             configuration.coupling_map = get_coupling_map_from_qc_topology(self.qc). # <-- this line

The line appears unrelated to any code I modified, and I am unable to tell whether the updates caused this or not. I cannot install the dependencies currently in main, as scipy fails to find BLAS and LAPACK, despite my best efforts. The most recent CI logs have been deleted, so I can't check there either.

[notmgsk]

What motivates the numpy (thus python > 3.7) upgrade?

[Shadow53]

What motivates the numpy (thus python > 3.7) upgrade?

numpy is one of the packages with a security vulnerability

[rigetti-githubbot]

:tada: This PR is included in version 0.4.6 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: