Add issue template for performance optimization category (kuzudb#3535)

* fix the result of OrderByFlatUnflat1 on all platforms

* add issue template for performance optimization

* rename title prefix

* new line

.github/ISSUE_TEMPLATE/optimization.yml

@@ -0,0 +1,17 @@
+name: Performance optimization suggestion
+description: Suggestion a new performance optimization idea for Kùzu
+title: "Optimization: "
+labels: [performance optimization]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Share a new idea for improving Kùzu's performance.
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: |
+        Describe the idea and why it would be useful.
+    validations:
+      required: true

test/test_files/tinysnb/order_by/single_label.test

@@ -318,10 +318,21 @@ Elizabeth
 7|8
 
 -LOG OrderByFlatUnflat1
--STATEMENT MATCH (p:person)-[:knows]->(p1:person) return p.ID, p1.ID ORDER BY p.ID limit 3
+-STATEMENT MATCH (p:person)-[:knows]->(p1:person) return p.ID, p1.ID ORDER BY p.ID, p1.ID
 -CHECK_ORDER
 -ENUMERATE
----- 3
+---- 14
 0|2
 0|3
 0|5
+2|0
+2|3
+2|5
+3|0
+3|2
+3|5
+5|0
+5|2
+5|3
+7|8
+7|9