Remove an unnecessary line break for PULL_REQUEST_TEMPLATE.md
Remove an unnecessary line break for PULL_REQUEST_TEMPLATE.md

This is a trivial change.

Unnecessary line breaks are not made when displaying as a Markdown resource.
https://github.com/rubocop-hq/rubocop/blob/v0.72.0/.github/PULL_REQUEST_TEMPLATE.md

However, unnecessary line breaks are added when opening and opened PR pages.
e.g. https://github.com/rubocop-hq/rubocop/pull/7203

This PR removes an unnecessary line break from confirmation items
when opening a PR.

jfelchner/rubocop,deivid-rodriguez/rubocop,deivid-rodriguez/rubocop,rrosenblum/rubocop,tdeo/rubocop,rrosenblum/rubocop,meganemura/rubocop,jmks/rubocop,tejasbubane/rubocop,tdeo/rubocop,meganemura/rubocop,jmks/rubocop,smakagon/rubocop,deivid-rodriguez/rubocop,bbatsov/rubocop,jfelchner/rubocop,maxjacobson/rubocop,panthomakos/rubocop,bbatsov/rubocop,maxjacobson/rubocop,tdeo/rubocop,meganemura/rubocop,smakagon/rubocop,jmks/rubocop,tejasbubane/rubocop,jfelchner/rubocop,rrosenblum/rubocop,tejasbubane/rubocop,panthomakos/rubocop,maxjacobson/rubocop,panthomakos/rubocop