Sweep: Update README.md to reflect new code changes

[sweep-ai]

Purpose

This pull request updates the README.md file to be consistent with the changes made to the src/index.ts module and the examples in the example/rates-example.js file.

Description

The changes made in this pull request include:

1. Updated the example code in the "Getting a rate by code" section to use the promise-based approach and log the code along with the rate/error.
2. Updated the "Getting all the rates" section to use the promise-based approach and log the rates/error.
3. Updated the "Available Codes" section to reflect the latest update date of June 9, 2023.

Summary

The changes made in this pull request are:

• Updated the README.md file
• Improved the example code for getting rates by code and all rates
• Updated the "Available Codes" section with the latest update date

Fixes #263.

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[colkito]

Sweep: check and fix the new conflicts in the README.md file.

[sweep-ai]

❌ Failed to make changes:

The exception message is:'Repository' object has no attribute 'repo'

The stack trace is:Traceback (most recent call last):
File "/app/sweepai/handlers/on_comment.py", line 350, in on_comment
commit = commit_multi_file_changes(cloned_repo.repo, new_file_contents_to_commit, commit_message, branch_name)
File "/app/sweepai/utils/github_utils.py", line 233, in commit_multi_file_changes
repo = cloned_repo.repo
AttributeError: 'Repository' object has no attribute 'repo'

Please report this on our community forum.

This is an automated message generated by Sweep AI.