CI: force isntall cargo audit
We are caching $CARGO_HOME inbetween rus, so an arbitrary cargo audit binary might already exist in the environment. Force install it so cargo doesn't complain and our binary is guaranteed "fresh".
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We are caching $CARGO_HOME inbetween rus, so an arbitrary cargo audit binary might already exist in the environment. Force install it so cargo doesn't complain and our binary is guaranteed "fresh".