On macOS, files in Contents/PlugIns/ need to be codesigned individually.
Since Lua plugins are not really binaries, per Apple's documentation
that is to be avoided (and we currently only sign executables there).
Just move Lua plugins generally to the resources directory, like we do
for other scripts like the debugger Python scripts, and load them from
there.
Change-Id: Idabd6b7c0c7c6e842b1752488cb7073f00e7be49
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>
