chore: update workflow file (#249)

Co-authored-by: Robin Salkeld <[email protected]>

Author: josecorella

.github/workflows/ci_test_net.yml

@@ -26,7 +26,8 @@ on:
 jobs:
   testDotNet:
     # Don't run the nightly build on forks
-    if: github.event_name != 'schedule' || github.repository_owner == 'awslabs'
+    # Disabled until we reintroduce DynamoDbEncryption, since a matrix vector cannot be empty
+    if: false && (github.event_name != 'schedule' || github.repository_owner == 'awslabs')
     strategy:
       matrix:
         library: [