Cucumber tests: Convert Travel agency test to not use example yaml from operator repository

Right not Travel agency Cucumber test uses example yaml file from Kogito operator repository.

However this example yaml points to default branch. Considering that Travel agency is moved to Kogito examples repository the default branch is `stable`.

Our tests need to run the Travel agency on master branch to make sure it works with latest changes. As there may be significant changes between stable and master branches the Travel agency needs to be created dynamically, similar way to other existing examples.