fix: jsx_curly_braces flagging trailing space expression

[marvinhagemeister]

The jsx-curly-braces rule should not flag string literal expression children when they're at the end of a line and a child is following after it. This is a common pattern to preserve whitespace as HTML whitespace rules would trim it otherwise.

// Valid
<div>
  foo{" "}
  <span />
</div>

[kitsonk]

Just found this one too, so won't open an issue.