[windows] Some hard-coded PREFIX(s) are not being patched by conda-build

I just wanted to bring this to the core team's attention.

https://github.com/conda/conda-build/issues/3909#issuecomment-626586540

In the recent `conda-build` releases, there is a regression which caused some PREFIX(s) not being detected during the packaging phase (For example, [`sip`](https://github.com/conda-forge/sip-feedstock) and [`pyqt`](https://github.com/conda-forge/pyqt-feedstock)), and which consequently causes [build breaks](https://github.com/conda-forge/orocos-kdl-feedstock/pull/1#issuecomment-631811948) of the downstream project.

Based on the comment from `conda-build`, it is planned to be addressed in the next release which is `conda-build 3.19.4`. Once it is released, some feedstock would need a rebuild to get it fixed.