Don't try to build rapidjson

rapidjson as a submodule won't build in our environment due
to old CMake version requirements, and since it's a header-only
library, we only need the headers to be present to allow
opentimelineio to build.

Signed-off-by: Jean-Francois Panisset <panisset@gmail.com>

Author: jfpanisset

src/deps/CMakeLists.txt

@@ -33,9 +33,7 @@ if(NOT OTIO_FIND_PYBIND11 AND OTIO_PYTHON_INSTALL)
     add_subdirectory(pybind11)
 endif()
 
-if(NOT OTIO_FIND_RAPIDJSON)
-    add_subdirectory(rapidjson)
-endif()
+# Don't try to build rapidjson, it won't, and since it's header-only, we don't need to built id.
 
 if(NOT OTIO_FIND_IMATH)
     # preserve BUILD_SHARED_LIBS options for this project, but set it off for Imath