Search conan executable in the default installer location

[nolange]

The official Windows installer [1] by default installs conan to %ProgramFiles%\Conan\conan\conan.exe. Add this subdirectory to the find_package call on Windows.

[1] - https://conan.io/downloads

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[nolange]

no, putting stuff in path is a really bad idea, windows will search DLLs there.

if you dont have conan in path, the script wont work obviously