docs: Add example that demonstrates multiple search queries

[Okabe-Junya]

resolved #49

WHAT I CHANGED

• added an example to the README. This consolidates the metrics from multiple repos into a single report.

FUTURE WORK

This example is working well, but there may be some potential problems. These might become challenges in the future.

• Unexpected references might occur and be treated as spam (as shown in the example I provided in the issue).
• The use of the chown command within the workflow might pose a security risk. (I'm not a security expert, so I don't know the details, but...)
• The workflow has become a bit verbose. It might be more considerate to provide functionality to make it shorter.
• Including private repos might be a bit challenging. Is there a good way to deal with this?

[zkoppert]

Looks fantastic! Thanks for adding this along with all your other submissions! Greatly appreciated! 🎉