Keep github template helper text visible only to the issue author (dd…

…ev#3029) [skip ci][ci skip]

.github/ISSUE_TEMPLATE/Feature_request.md

@@ -8,13 +8,13 @@ assignees: ''
 ---
 
 **Is your feature request related to a problem? Please describe.**
-A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+<!-- A clear and concise description of what the problem is. Ex. I'm always frustrated when [...] -->
 
 **Describe the solution you'd like**
-A clear and concise description of what you want to happen.
+<!-- A clear and concise description of what you want to happen. -->
 
 **Describe alternatives you've considered**
-A clear and concise description of any alternative solutions or features you've considered.
+<!-- A clear and concise description of any alternative solutions or features you've considered. -->
 
 **Additional context**
-Add any other context or screenshots about the feature request here.
+<!-- Add any other context or screenshots about the feature request here. -->