quick credential update for readme

[brok3turtl3]

Description

This PR updates the readme file to reflect currently available login credentials.

Jira Task

N/A

Testing Instructions

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Checklist

Please go through each item of this checklist carefully.

All Team Members

• I added a descriptive title to this PR.
• I filled out the Description, Jira Task, and Testing Instructions sections above.
• I added or updated [Jest unit tests]for any changes to components, server-side controllers, etc.
• I ran npm run docker-test in my local environment to check that this PR passes all unit tests.
• I checked to ensure my code changes follow the recommended style guide.

Additional Notes, Images, etc.

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