Existing files should be removed when switching from portal created JavaScript functions to GitHub deployed functions

Repro:

Create a JS function on Azure on a new Function App (HttpTriggerJS1 in my case):

Create a new repo on GitHub, configure the Function App to be deployed by that repo, and kick off a deployment by commiting a locally created JavaScript function to the repo (called httpTrigger in my case):

Once the deploy is finished you will see both functions there, meaning the old content that was there from when it was created from the portal was not removed as part of the deployment:

Customer's expectation was that the code coming from GitHub would be the source of truth and old functions created via the portal would be removed

This might happen with CSX too but haven't tested.