Fix create_image.sh

Author: DiegoMzmn

docker/create_image.sh

@@ -2,6 +2,7 @@ cd ../frontend
 npm install
 npm audit fix
 npm run build --prod --baseHref=http://localhost:8080/
+cp -a dist/openvidu-teaching/. ../backend/src/main/resources/static/
 cd ../backend
 mvn -Dmaven.test.skip=true package
 cp target/OpenViduTeaching.jar ../docker/build/