Implement reauthorization for Cloud Integrations

[axosoft-ramint]

We have flows in GitLens for reauthorizing a token (for example, notification of 'your token is invalid or expired. Would you like to try reauthenticating?'). When using cloud integrations, this currently just opens the /connect flow and doesn't change anything about the token.

To fully reauth, the client should:

1. Wipe the local session for the cloud integration
2. Call the backend route to delete the token
3. Call /connect which would then allow the user to re-auth with that provider and use the new token.