while deploying app service unable to set DOCKER_REGISTRY_SERVER_PASSWORD and fail to upgrade az

### **This is autogenerated. Please review and update as needed.**

## Describe the bug

**Command Name**
`az webapp create --resource-group MyRG --plan ASPlan --name ASname --deployment-container-image-name MyACR.azurecr.io/app:latest --docker-registry-server-user ACRadmin --docker-registry-server-password string`
or
`az webapp config appsettings set -resource-group MyRG --name ASname --settings WEBSITES_PORT=5000 DOCKER_REGISTRY_SERVER_PASSWORD=string`
and
`az upgrade`
**Errors:**
after run either az webapp create or config command, output:
```
{
"name": "DOCKER_REGISTRY_SERVER_PASSWORD",
"slotSetting": false,
"value": null
}

```
after run az upgrade
```
This command is in preview and under development. Reference and support levels: https://aka.ms/CLI_refstatus
Your current Azure CLI version is 2.33.1. Latest version available is 2.34.1.
Please check the release notes first: https://docs.microsoft.com/cli/azure/release-notes-azure-cli
Do you want to continue? (Y/n): y
Hit:1 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:2 https://dl.yarnpkg.com/debian stable InRelease
Hit:3 http://security.ubuntu.com/ubuntu hirsute-security InRelease
Hit:4 https://deb.nodesource.com/node_14.x hirsute InRelease
Hit:5 http://us.archive.ubuntu.com/ubuntu hirsute InRelease
Hit:6 http://us.archive.ubuntu.com/ubuntu hirsute-updates InRelease
Hit:7 http://us.archive.ubuntu.com/ubuntu hirsute-backports InRelease
Hit:8 https://packages.microsoft.com/repos/azure-cli hirsute InRelease
Err:9 https://apt.releases.hashicorp.com hirsute InRelease
Temporary failure resolving 'apt.releases.hashicorp.com'
Reading package lists... Done
W: Failed to fetch https://apt.releases.hashicorp.com/dists/hirsute/InRelease Temporary failure resolving 'apt.releases.hashicorp.com'
W: Some index files failed to download. They have been ignored, or old ones used instead.
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
azure-cli is already the newest version (2.33.1-1~hirsute).
0 upgraded, 0 newly installed, 0 to remove and 10 not upgraded.
CLI upgrade failed or aborted.
```
## To Reproduce:
Steps to reproduce the behavior. Note that argument values have been redacted, as they may contain sensitive information.

run the command I have type above, do not forget to change resource group name , app name, app service plan id, Azure Container Registry (ACR) hostname, ACR user and ACR password

run az upgrade

## Expected Behavior
the webapp should contains DOCKER_REGISTRY_SERVER_PASSWORD=string in Application Settings at the beginning and able to visit the webapp immediately
upgrade az
## Actual Behavior
the webapp DOCKER_REGISTRY_SERVER_PASSWORD in Application Settings is null at the beginning and have to wait about 3 mins to look for and get password by itself, to pull image from ACR

upgrade az actual behavior is on above
## Environment Summary
```
Linux-5.11.0-49-generic-x86_64-with-debian-bullseye-sid, Ubuntu 21.04
Python 3.6.10
Installer: DEB

azure-cli 2.33.1 *
```
## Additional Context