fix(users): Added merchant name is list merchants

[racnan]

Type of Change

• Bugfix
• New feature
• Enhancement
• Refactoring
• Dependency updates
• Documentation
• CI/CD

Description

Added Merchant name in list merchant api.
PR to main: #3289

Additional Changes

• This PR modifies the API contract
• This PR modifies the database schema
• This PR modifies application configuration/environment variables

Motivation and Context

Dashboard needs to show merchant name is available.

How did you test it?

curl --location --request GET '<URL>/user/switch/list' \
--header 'Authorization: Bearer <JWT>'

Above api should return list of merchant accounts the user (whos jwt is being used) has access to.

[
    {
        "merchant_id": "merchant_1704706726",
        "merchant_name": null
    },
    {
        "merchant_id": "merchant_1704706837",
        "merchant_name": "some merchant name"
    }
]

Checklist

• I formatted the code cargo +nightly fmt --all
• I addressed lints thrown by cargo clippy
• I reviewed the submitted code
• I added unit tests for my changes where possible
• I added a CHANGELOG entry if applicable

[racnan]

PR to main: #3289