Actions: Add change note for removing model ggenerator queries

Author: adityasharad

actions/ql/src/change-notes/2025-04-24-model-generator-queries.md

@@ -0,0 +1,14 @@
+### Breaking Changes
+
+* The following queries have been removed from the `security-and-quality` suite.
+  They are not intended to produce user-facing
+  alerts describing vulnerabilities.
+  Any existing alerts for these queries will be closed automatically.
+  * `actions/composite-action-sinks`
+  * `actions/composite-action-sources`
+  * `actions/composite-action-summaries`
+  * `actions/reusable-workflow-sinks`
+    (renamed from `actions/reusable-wokflow-sinks`)
+  * `actions/reusable-workflow-sources`
+  * `actions/reusable-workflow-summaries`
+