Add 2 more passing non-interactive scripts (012, 015)

Author: mwunderl

tuts/012-transitgateway-gettingstarted/REVISION-HISTORY.md

@@ -10,3 +10,7 @@
 - Type: functional
 - Remove SDK content from CFN branch (belongs on SDK branches)
 
+
+### 2026-04-28 v-ni1 non-interactive
+- Type: functional
+- Made script fully non-interactive for automated testing