Add r2 list objects

[ferhatelmas]

Description

Add missing R2 list objects support.
Came up in wrangler, wanted to add it here too but it's not a part of publicly documented API so feel free to close.

Has your change been tested?

Yes

Screenshots (if appropriate):

Types of changes

What sort of change does your code introduce/modify?

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• This change is using publicly documented in cloudflare/api-schemas
  and relies on stable APIs.

[github-actions]

changelog detected ✅

[jacobbednarz]

closing this for now due to missing public documentation. if we can get the endpoints documented, this will automatically make it's way into v2.