codecatalyst: can't log in: "[error] Failed submitting credentials"

## Problem

Trying to login to CodeCatalyst from the vs code extension. I have an iam role with full access to codecatalyst. When I enter credentials, a box with the word "object" appears. Output tab shows error message:

```
2024-06-27 08:42:20.569 [info] auth: Updating connection state of temp:495f884972650811629c5fb913c55f1c017541b34fd018d36f449c21a8542694 to authenticating

2024-06-27 08:42:21.280 [info] auth: Updating connection state of temp:495f884972650811629c5fb913c55f1c017541b34fd018d36f449c21a8542694 to valid

2024-06-27 08:42:21.293 [error] Failed submitting credentials
```

## Steps to reproduce the issue

I'm not sure how to reproduce it. I don't find any other reports of these symptoms online.

## Expected behavior

I should be able to login to codecatalyst from the vscode extension.

## System details (run `AWS: About` and/or `Amazon Q: About`)

- OS: Mac os 12
- Visual Studio Code version: 1.90.2
- AWS Toolkit version:
- Amazon Q version:

The report names the VS Code extension, its Output tab, and the AWS: About/Amazon Q: About commands, but no source file or test. First capture the missing version details and establish a reproducible CodeCatalyst login flow; done means credentials submit successfully without the “object” box or error.

Written by the indexing model from the issue text.