Apply suggestions from code review

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

packages/npm/openapi.sh

@@ -2,6 +2,8 @@
 
 # Script to generate OpenAPI typescript definitions for the Matrix APIs
 
+set -e
+
 RELEASE="${npm_package_version%.*}"
 SPEC_DIR="v${RELEASE}"
 if [ "$RELEASE" == "0.0" ]; then