`refmt` breaks with multiline comment and OCaml 4.08 Binding operators

[rohitkg98]

When let* is used after a multiline comment, refmt signals an Unclosed "{" ... error.

Check an example of such code here: https://github.com/esy/esy/blob/master/test-e2e-re/lib/Helpers.re#L57

I rectified the current issue by using Single Line comments instead: esy/esy@0271ffa#diff-d48981202dea0e43079feef93f441a8dc5b5a093b53d08c29adc7f5875bd0645L56