Fix auditwheel libpython check on Python 3.7 and older versions

[messense]

Found in https://github.com/PyO3/maturin/actions/runs/3360316035/jobs/5569360257

🐍 Found CPython 3.7m at /opt/hostedtoolcache/Python/3.7.15/x64/bin/python
⚠️  Warning: Couldn't find the symbol `PyInit_pyo3_no_extension_module` in the native library. Python will fail to import this module. If you're using pyo3, check that `#[pymodule]` uses `pyo3_no_extension_module` as module name
🖨  Copied external shared libraries to package pyo3_no_extension_module.libs directory:
    /opt/hostedtoolcache/Python/3.7.15/x64/lib/libpython3.7m.so.1.0
📦 Built wheel for CPython 3.7m to test-crates/targets/pyo3_no_extension_module/pyo3_no_extension_module-2.1.0-cp37-cp37m-manylinux_2_5_x86_64.manylinux1_x86_64.whl

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