Disable Swagger

[JaimieWi]

Swagger UI is a github environment variable - we want to disable it for security

microsoft/AzureTRE#2981

Variable	Description
ENABLE_SWAGGER	Determines whether the Swagger interface for the API will be available.
SWAGGER_UI_CLIENT_ID	Generated when following pre-deployment steps guide. Client ID for swagger client to make requests.

https://microsoft.github.io/AzureTRE/latest/tre-admins/environment-variables/#for-azure-tre-instance-in-configyaml