github: Update bug_report.md

.github/ISSUE_TEMPLATE/bug_report.md

@@ -13,10 +13,8 @@ Vulkan-Headers exists as a publishing mechanism for headers and related material
 
 - https://github.com/KhronosGroup/Vulkan-Docs - C headers, XML, validusage.json, and generation scripts
 - https://github.com/KhronosGroup/Vulkan-Hpp - C++ headers
-- This repository - Repository structure, management, and build system *only*
-
-See the repository README for more details.
 
+The CONTRIBUTING.md contains a list of files this repo owns.
 
 **Describe the bug**
 
@@ -30,3 +28,17 @@ If applicable, add screenshots to help explain your problem.
 
 **Additional context**
 Add any other context about the problem here.
+
+**Code**
+
+<details>
+<summary>code or terminal output</summary>
+
+```cpp
+int main()
+{
+    return 0;
+}
+```
+
+</details>