github: update bug report template

improved formatting & clarity

.github/ISSUE_TEMPLATE/bug-report.md

@@ -1,32 +1,36 @@
 ---
 name: bug report
-about: report an issue with downloads or something else
-title: ''
+about: report a global issue with the cobalt codebase
+title: '[short description of the bug]'
 labels: bug
 assignees: ''
 
 ---
 
-**bug description**
-a clear and concise description of what the bug is.
+### bug description
+clear and concise description of what the issue is.
 
-**reproduction steps**
-steps to reproduce the behavior:
+### reproduction steps
+steps to reproduce the described behavior.  
+here's an example of what it could look like:
 1. go to '...'
 2. click on '....'
-3. download this video: **[link here]**
+3. download [media type] from [service]
 4. see error
 
-**screenshots**
-if applicable, add screenshots or screen recordings to help explain your problem.
+### screenshots
+if applicable, add screenshots or screen recordings to support your explanation.  
+if not, remove this section.
 
-**links**
+### links
 if applicable, add links that cause the issue. more = better.  
+if not, remove this section.
 
-**platform**
+### platform information
 - OS [e.g. iOS, windows]
 - browser [e.g. chrome, safari, firefox]
 - version [e.g. 115]
 
-**additional context**
-add any other context about the problem here.
+### additional context
+add any other context about the problem here if applicable.  
+if not, remove this section.