`network`: Express Route Gateway Create failed with `GwmOperationTimeOut`

when create a express route gateway with `AutoScaleConfigurationBounds.Min` > 1, it will be high possibility response an error as:

```
Error: waiting for creation of Express Route Gateway: (Name "acctestER-gateway-221128051342042195" / Resource Group "acctestRG-express-221128051342042195"):
Code="GwmOperationTimeOut"
Message="Operation timed out. Please retry after some time or contact support."
Details=[]
```

Start by reproducing Express Route Gateway creation with AutoScaleConfigurationBounds.Min greater than 1, then inspect the relevant Express Route Gateway REST API specification. Done means the gateway can be created without the GwmOperationTimeOut response; the issue does not name a file or test to run.

Written by the indexing model from the issue text.