There's no point for the intermediate `getPath` function calling
`getLuaPath` with the "lua" argument.
There's also no other nginx test this copies code from.
We always call `getLuaPath` with "lua", so constant-propagate it in.
Also, camel-case `lualibs` to `luaLibs.`
nginx lua needs resty
the enableSandbox option of nginx was removed in 535896671b
the test fails with
```
vm-test-run-nginx-sandbox> machine # [ 47.753580] nginx[1142]: nginx: [alert] detected a LuaJIT version which is not OpenResty's; many optimizations will be disabled and performance will be compromised (see https://github.com/openresty/luajit2 for OpenResty's LuaJIT or, even better, consider using the OpenResty releases from https://openresty.org/en/download.html)
vm-test-run-nginx-sandbox> machine # [ 47.756064] nginx[1142]: nginx: [alert] failed to load the 'resty.core' module (https://github.com/openresty/lua-resty-core); ensure you are using an OpenResty release from https://openresty.org/en/download.html (reason: module 'resty.core' not found:
vm-test-run-nginx-sandbox> machine # [ 57.911766] systemd[1]: Failed to start Nginx Web Server.
```