union types: fix trailing comment causing multiline when preferSingleLine is true

[declanvong]

has_any_node_comment_on_different_line doesn't currently consider the case where the final node has a trailing line comment (which is therefore on the same line).

This causes issues such as the following, where we see union types randomly get multi-lined when we add a trailing comment:

Input:

function f(
    arg: '1' | '2',
    otherArg: string,
) { }

add a // todo: fix me after arg: '1' | '2',

Output:

function f(
  arg:
    | '1'
    | '2', // todo: fix me
  otherArg: string,
) { }

Expected:

function f(
    arg: '1' | '2', // todo: fix me
    otherArg: string,
) { }

This PR fixes that by allowing a trailing line comment for the last node in the node list.

I've added tests for this case (union / intersection types), and these are the the most obvious cases I've seen so far, but it's probable that this affects many other collections as well.