C#: Add change note

2021-04-14 09:22:16 +02:00 · 2021-04-14 09:22:16 +02:00 · 36fe72246b
--- a/csharp/change-notes/2021-04-14-customizations.md
+++ b/csharp/change-notes/2021-04-14-customizations.md
@ -0,0 +1,2 @@
+lgtm,codescanning
+* A new library, `Customizations.qll`, has been added, which allows for global customizations that affect all queries.