Loco starter move fixtures to root folder instead of src

[anhnmt]

When building the docker image I encountered the following situation:

--/
----/assets
----/config
----/src/fixtures
----/app-cli

I think it would be better to put fixtures in the root folder instead of src:

--/
----/assets
----/config
----/fixtures
----/app-cli

My current method is to edit the source code, but I should do the same for the starter loco

let path = std::path::Path::new("./fixtures");
db::run_app_seed::<App>(app_context, path).await?;
Ok(())