chore: add maintenance label to maintenance GitHub template (#135)

Signed-off-by: Joel Wong <[email protected]>

Author: joel-wong-aws

.github/ISSUE_TEMPLATE/maintenance.yml

@@ -1,7 +1,7 @@
 name: "🛠️ Maintenance"
 description: Some type of improvement
 title: "Maintenance: (short description of the issue)"
-labels: ["needs triage"]
+labels: ["maintenance", "needs triage"]
 body:
   - type: textarea
     id: description