Format generated boilerplate files for access modifiers on separate line

[chasefleming]

If you generate a boilerplate file like a script with flow generate script ... it will create a file like this;

access(all) fun main() {}

It seems the pattern everyone is following is not to have a line break like this:

access(all)
fun main() {}

Let's update the boilerplate for scripts and contracts to match this.