Minor Fix to the Put Config API Endpoint

[MinuraPunchihewa]

Description

This PR makes a minor fix to the PUT /integrations/ endpoint to convert the path of the credential file passed to a string. This was necessary to get the handler authentication from YouTube to work as the path was being initialized as a PosixPath.

Fixes #issue_number

Type of change

• 🐛 Bug fix (non-breaking change which fixes an issue)

Verification Process

To ensure the changes are working as expected:

• Test Location: Specify the URL or path for testing.
• Verification Steps: Outline the steps or queries needed to validate the change. Include any data, configurations, or actions required to reproduce or see the new functionality.

Checklist:

• My code follows the style guidelines(PEP 8) of MindsDB.
• I have appropriately commented on my code, especially in complex areas.
• Necessary documentation updates are either made or tracked in issues.
• Relevant unit and integration tests are updated or added.