Don't fail when fail to convert to abs path

[clee2000]

There are some non utf8? paths in my checkout of pytorch

(forpytorch) ls third_party/opentelemetry-cpp/third_party/prometheus-cpp/3rdparty/civetweb/test/nonlatin
𞤀𞤣𞤤𞤢𞤥 𞤆𞤵𞤤𞤢𞤪.txt                               这是一个示例文本.html

which cause lintrunner --all-files to fail for me.

Idk if this is a good idea

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cargo build
lintrunner/target/debug/lintrunner