Clean up: add rai_results to gitignore, remove unused rai_test.py

- .gitignore: Add rai_results/ to ignore RAI evaluation output files
- Remove content-gen/scripts/rai_test.py (duplicate of tests/rai_testing.py)

Author: hunterjam

.gitignore

@@ -65,4 +65,8 @@ Thumbs.db
 pdf
 *.bak
 *.tmp
-*.zip
+*.zip
+
+# RAI evaluation results
+rai_results/
+**/rai_results/