Update changelog for 2.7.4

Dekker1 · Dekker1 · commit 7f922b704bda · 2023-05-11T11:35:30.000+10:00
diff --git a/MiniZincIDE/CHANGES b/MiniZincIDE/CHANGES
@@ -1,3 +1,7 @@
+2023-05-11
+  v2.7.4
+-  Update to MiniZinc 2.7.4.
+
 2023-04-20
   v2.7.3
 -  Only show MOOC error code when response is actually an error (#176).
