fix(deps): allow protobuf < 5.0.0

[parthea]

fix(deps): require proto-plus >= 1.22.0

[unforced]

=================================== FAILURES ===================================
______________________ TestComputeSmoke.test_zero_values _______________________

self = <test_smoke.TestComputeSmoke testMethod=test_zero_values>

    def test_zero_values(self):
        with self.assertRaises(expected_exception=TypeError) as ex:
            self.client.get(instance=self.name, zone=0)
>       self.assertIn(
            "0 has type int, but expected one of: bytes, unicode",
            str(ex.exception.args),
        )
E       AssertionError: '0 has type int, but expected one of: bytes, unicode' not found in "('bad argument type for built-in operation',)"

tests/system/test_smoke.py:77: AssertionError
- generated xml file: /tmpfs/src/github/python-compute/system_3.8_sponge_log.xml -
=========================== short test summary info ============================
FAILED tests/system/test_smoke.py::TestComputeSmoke::test_zero_values - Asser...

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