Keyvault service set up not working

[mydiemho]

This is a Bug Report

Description

Function app doesn't have access to keyvault if it was set up through serverless.

Here's a [walk through to try it out yourself(https://github.com/mydiemho/myho-serverless-demo/blob/saveKeyVaultSyntax/README.md)

This seems to be un-deterministic, 1/10 times it works! so if you got it working, please try again with different app/keyVault

Additional Data

• Serverless Framework Version you're using:
• Serverless CLI Version you're using:
• Serverless Azure Plugin Version you're using:
• Operating System:
• Stack Trace:
• Provider Error messages: