Fix listPaginated example in README

[austin-denoble]

Problem

Was reviewing the outgoing docs changes for list support and realized the code examples in the README were calling .list() rather than .listPaginated().

Solution

Update the README.

Type of Change

• [ ] 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 not work as expected)
• [ ] This change requires a documentation update
• [ ] Infrastructure change (CI configs, etc)
• [X] Non-code change (docs, etc)
• [ ] None of the above: (explain here)