issue template: Ask if uvloop behaves differently from vanilla asyncio

Author: 1st1

.github/ISSUE_TEMPLATE.md

@@ -12,5 +12,6 @@ Thank you!
 * **Python version**:
 * **Platform**:
 * **Can you reproduce the bug with `PYTHONASYNCIODEBUG` in env?**:
+* **Does uvloop behave differently from vanilla asyncio? How?**:
 
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