Use single FRT

[juan-arias]

Proposed changes

Update the use of family refresh tokens, and instead use a single family refresh token.

Type of change

• Feature work
• Bug fix
• Documentation
• Engineering change
• Test
• Logging/Telemetry

Risk

• High – Errors could cause MAJOR regression of many scenarios. (Example: new large features or high level infrastructure changes)
• Medium – Errors could cause regression of 1 or more scenarios. (Example: somewhat complex bug fixes, small new features)
• Small – No issues are expected. (Example: Very small bug fixes, string changes, or configuration settings changes)

Additional information

[azure-pipelines]

This pull request does not update changelog.txt.

Please consider if this change would be noticeable to a partner or user and either update changelog.txt or resolve this conversation.