fixing link of `c_cxx/fns_candy_style_transfer` (#13516)
### Description
Updating an invalid link :
The link for `samples/c_cxx/fns_candy_style_transfer` was invalid. The
files now seems to be present in the `onnxruntime-inference-examples`
repo -
https://github.com/microsoft/onnxruntime-inference-examples/tree/main/c_cxx/fns_candy_style_transfer
### Motivation and Context
Fixing a non-working link.
