conan package install error: 'ConanOutput' object has no attribute 'warn'

[shaqtsui]

Error details:

ERROR: packio/2.5.0: Error in configure() method, line 89
        self.output.warn("packio requires C++17. Your compiler is unknown. Assuming it supports C++17.")
        AttributeError: 'ConanOutput' object has no attribute 'warn'

cause analysis:
warn() in https://github.com/conan-io/conan-center-index/blob/master/recipes/packio/all/conanfile.py#L89C18-L89C24 doesn't exist in conan 2.0 api https://docs.conan.io/2/reference/conanfile/running_and_output.html

[qchateau]

Hello, I have tried to fix it but it seems this is not the only incompatibility with conan 2.0.
I don't use conan 2.0 so my knowledge of the migration process is limited. That said you are free to fix the recipe on CCI, I'd appreciate the contribution.