Remove references to CPPINTEROP_BUILD_DIR in Emscripten build #530
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Description
Please include a summary of changes, motivation and context for this PR.
Given we need to install CppInterOp as part of the xeus-cpp-lite build process we don't really need to reference CPPINTEROP_BUILD_DIR anymore, since it will be found in the PREFIX folder.
Fixes # (issue)
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