ISSUE_TEMPLATE: Remove line breaks

The GitHub issue editor interprets each one literally, regardless of
paragraph status, which is annoying.

Author: mbland

.github/ISSUE_TEMPLATE.md

@@ -1,12 +1,8 @@
 ## Due diligence
 
-- [ ] I am familiar with the ["Reporting issues" section of
-  CONTRIBUTING.md][reporting]
-- [ ] I have searched the [existing issues][issues] and haven't found one
-  that matches what I'm reporting or requesting now.
-- [ ] If this is a bug report, I have searched the [Bash changelog][changes]
-  for information that may explain or provide clues to the behavior I'm
-  observing and reference it in the body of the report.
+- [ ] I am familiar with the ["Reporting issues" section of CONTRIBUTING.md][reporting]
+- [ ] I have searched the [existing issues][issues] and haven't found one that matches what I'm reporting or requesting now.
+- [ ] If this is a bug report, I have searched the [Bash changelog][changes] for information that may explain or provide clues to the behavior I'm observing and reference it in the body of the report.
 
 [reporting]: https://github.com/mbland/go-script-bash/blob/master/CONTRIBUTING.md#reporting-issues
 [issues]:    https://github.com/mbland/go-script-bash/issues
@@ -26,5 +22,4 @@ Otherwise remove this section altogether.
 
 Replace this text with a description of your bug report or feature request.
 
-If this is a bug report, include any relevant command line steps, code snippets,
-or test cases to reproduce the issue.
+If this is a bug report, include any relevant command line steps, code snippets, or test cases to reproduce the issue.