az post upgrade apim platform version to stv2 err saying it already is that version

New issue created because `0` results when searching for `migrateToStv2`.

**Related command**
```
$ az rest --method post --uri "/subscriptions//resourceGroups//providers/Microsoft.ApiManagement/service//migrateToStv2?api-version=2022-08-01"
```

**Describe the bug**
Above command returns the following

```
Bad Request({"error":{"code":"NotSupported","message":"Service is already on stv2.","details":null,"innerError":null}})
```

despite it is still `stv1` for the Platform Version.

```
$ az apim show --name -g --query platformVersion --output tsv
stv1

```

**To Reproduce**
1. Run the above command on an apim instance in the Developer Tier.

**Expected behavior**
No errors. Migration should happen in 10-15 minutes like it does for our other APIM instancs. The same command is successful at upgrading from `stv1` to `stv2` for (2) other APIM instances we have in the Basic tier

**Environment summary**
`azure-cli` version `2.47.0 *`
To recap: working on apim instances in the Basic tier. Not working on an APIM instance we have in the Developer tier.

**Additional context**