Currently the python unit test framework expects to find extension modules under the libtool build path '.libs'. CMake doesn't export its built libraries under a '.libs' sub-directory.
e.g.
CMake
ext/compressors/snappy/libwiredtiger_snappy.so
Libtool:
ext/compressors/snappy/.libs/libwiredtiger_snappy.so
Update the python unit test framework to also detect the library outside of the '.libs' sub-directory.