Combine recommendations examples

[laurachevalier4]

• Remove the apply_recommendation and get_text_ad_recommendations examples
• Merge the apply_recommendation example into the detect_and_apply_recommendations example
• Add new tags for developer guide to reference, in place of deleted get_text_ad_recommendations and to capture apply_recommendation tag logic that was moved into a separate function. I want to make sure we're showcasing the logic to override parameters, so the new tag build_apply_recommendation_operation will enable this.