Add note to hopefully prevent more duplicates

Author: boltgolt

.github/ISSUE_TEMPLATE/bug_report.md

@@ -11,6 +11,8 @@ _Please describe the issue in as much detail as possible, including any errors a
 
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+- [ ] I've searched for similar issues already, and my issue has not been reported yet.
 
-**Linux distribution (if applicable)**:
-**Howdy version**:
+Linux distribution (if applicable): 
+
+Howdy version: