feat: add listAllObjects method to S3Template

[Tooa]

📢 Type of change

• Bugfix
• New feature
• Enhancement
• Refactoring

📜 Description

This pull request adds the method listAllObjects(bucketName) to the S3Template class. The method listObjects(bucketName, prefix) was previously added in #831.

I have read the contribution guidelines below. However, this change is rather small and it didn't take a long time to implement. Its fine if you don't want the method added and close this PR. My goal was to get familiar with the setup, contributing other features for the S3Template in the future (with prior discussion).

Suggest your change in the Issues. Start writing code once the issue got approved by project maintainers.

💡 Motivation and Context

1. It is not immediately obvious what to pass for the prefix to the listObjects(...) method to retrieve all objects of the bucket. I played around with wildcards for a while, but this didn't work out. In the end, the solution is passing the empty string as prefix
2. findAllObjects() gives better context for the reader than listObjects("bucket", "")

Note: I decided against adding the detail as documentation to the listObjects(...) function, because of reason 2.

💚 How did you test it?

• Command ./mvnw verify passes

📝 Checklist

• I reviewed submitted code
• I added tests to verify changes
• [ ]~~ I updated reference documentation to reflect the change~~ (no documentation available)
• [ x] All tests passing
• [ x] No breaking changes

🔮 Next steps

For discussion if we want to remove the some from the JavaDoc here. Not sure if some is related to the 1.000 objects restriction or to the prefix filter.

Returns some or all (up to 1,000) of the objects in a bucket

[Tooa]

I don't think my changes are related to the build failure in CI here.

[maciejwalkowiak]

Thanks @Tooa !