az functionapp create - repeating steps removes running Function App package

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**Describe the bug**
Reusing the "az functionapp create" steps in provisioning the infrastructure has an adverse effect on existing function app code running inside. It complete removes the running code

**To Reproduce**
Create a function app
az functionapp create --plan %az-applanname% --resource-group %az-resourcegroup% --name %az-functionappname1% --os-type %az-funcappostype% --runtime %az-funcappruntime% --storage-account %az-storageacc% --disable-app-insights %az-appinsightsdisable%

Deploy a sample FA from Azure DevOps step "Azure Function" in a release pipeline. Using the default settings where subscription / App Type (Windows) and App name (created in the AZ step above)

Confirm the code is running by checking through the Azure Portal / Function Apps / Functions pane

Re-run
az functionapp create --plan %az-applanname% --resource-group %az-resourcegroup% --name %az-functionappname1% --os-type %az-funcappostype% --runtime %az-funcappruntime% --storage-account %az-storageacc% --disable-app-insights %az-appinsightsdisable%

Confirm the code is disappeared by checking through the Azure Portal / Function Apps / Functions pane. "No results" will be listed

**Expected behavior**
The "az functionapp create" should be idempotent and not affect the current running service or code inside that service if it already exists.

**Environment summary**
Azure CLI version 2.0.69
Azure DevOps website using "Azure FunctionApp" Task version 1

**Additional context**
No additional content