[REF] Include protected datasets in main query result TSV examples instead of separate file

[alyssadai]

• Closes Merge aggregate and non-aggregate dataset examples in query result TSVs #45
• Related to Update auto-generation of query result examples query-tool#368

Changes proposed in this pull request:

• Manually add two protected datasets (corresponding to https://github.com/neurobagel/neurobagel_examples/blob/main/api-responses/fapi_query_success_200.json) to the human-readable and machine-optimized result TSV files
  • This is a temporary solution and should be revisited in Update auto-generation of query result examples query-tool#368
• Remove the example cohort-participant-results-agg.tsv to avoid confusion about the # of files generated by the query tool and nature of dataset visibility in the files

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[rmanaem]

Thanks for the PR @alyssadai 🧑‍🍳