Update pip.md

[ForeverZyh]

Swap the order of $CUDNN_PATH/lib and CONDA_PREFIX/lib.

I was hitting an error, Loaded runtime CuD NN library: 8.1.0 but source was compiled with: 8.6.0.
I find out that my CONDA_PREFIX/lib contains libcudnn8.1.0 so TF will first use this version instead of the libcudnn8.6.0 installed in the CONDA_PREFIX/lib.

[8bitmp3]

@markmcd

[vijayasarathib]

Looks good to me! The change makes sense given the issue described with the CuDNN library versions. I approve this change.

[markmcd]

Not sure how prevalent this issue is, if you have any more context on how you got into that state it'd be helpful.

That said, this is harmless, and I am generally in favour of ordering $PATH vars by specificity, which this does.