Revert "[build] Partially revert 90904fa9dd96b65944ae402a12ccb81e681b5d44."

This reverts commit 93a35d1964dd5a3d4b8c1d301ce07868c5c69fe6.
Revert "Bump monomac/maccore for compilation fixes with mono 3.2.3+"

This reverts commit 90904fa9dd96b65944ae402a12ccb81e681b5d44.
This wasn't supposed to be pushed.