Using a managed system identity with an Azure Function, to connect to the storage account. The fix was as @user71030 mentioned, to add Host.Results to the logging configuration with a level of information. The invocations seem to be slow to appear, in my case it took 3 minutes for it to show up. It had appeared in the log trace table before it appeared in the invocations list.

"logLevel": {
  "default": "Warning",
  "Host.Results": "Information",
  "Function": "Information"
},