There is a build time race condition that requires usd/usd to be built before usd/sdr in order for the usd/usd/pyConversions.h header to be exported and available to build usd\sdr\wrapShaderMetadataHelpers.cpp.
This dependency is not expressed in usd\sdr\CMakeLists.txt so the build will randomly fail depending on the planned project order CMake writes in the build file.
More interesting is that this header does not seem to be required in wrapShaderMetadataHelpers.cpp so removing the offending line seems to be a valid fix. If the header was really required, then linking with the usd module would be required as well.