Moving the sysconfig file caused spidermonkey_78 to fail to build. We now symlink it instead.
This reverts commit 6a23dde75bd9bb0cdcc58477439aaf1e146e3623.
This breaks virtualenv https://github.com/NixOS/nixpkgs/issues/104483.
We should probably not move `_sysconfigdata` but just copy it for cross to
another place or output.
This reverts commit 11806b6ede420bbdb980ca1c36918b71e9ddc0a2.