Pipeline operation breaks in MySql Flexible server

## Description
Resource provider name is different between path (DBForMySql) and resource Id(DBforMySQL), which causes piping operations such as
`Get-AzMySqlFlexiblerServer | Remove-AzMySqlFlexibleServer`
not to work.
Please see the following http request and response for details

```
DEBUG: ============================ HTTP REQUEST ============================

HTTP Method:
GET

Absolute Uri:
https://management.azure.com/subscriptions/9e223dbe-3399-4e19-88eb-0975f02ac87f/resourceGroups/yemingtemp/providers/Microsoft.DBForMySql/flexibleServers?api-version=2020-07-01-preview

Headers:

Body:

DEBUG: BeforeCall:
DEBUG: ============================ HTTP RESPONSE ============================

Status Code:
OK

Headers:
Cache-Control : no-cache
Pragma : no-cache
X-Content-Type-Options : nosniff
x-ms-request-id : 00e390a6-a188-4913-a999-aa9c86561868
Server : Microsoft-HTTPAPI/2.0
x-ms-ratelimit-remaining-subscription-reads: 11995
x-ms-correlation-request-id : 70e7c07a-eccf-4581-8537-29c7c3ebba81
x-ms-routing-request-id : SOUTHEASTASIA:20201217T111831Z:70e7c07a-eccf-4581-8537-29c7c3ebba81
Strict-Transport-Security : max-age=31536000; includeSubDomains
Date : Thu, 17 Dec 2020 11:18:30 GMT

Body:
{
"value": [
{
"sku": {
"name": "Standard_B1ms",
"tier": "Burstable",
"capacity": 0
},
"properties": {
"administratorLogin": "mysql_test",
"storageProfile": {
"storageMB": 10240,
"storageIops": 0,
"backupRetentionDays": 7,
"storageAutogrow": "Disabled",
"fileStorageSkuName": "Premium_LRS"
},
"version": "5.7",
"state": "Ready",
"haState": "NotEnabled",
"fullyQualifiedDomainName": "mysql-test-100.mysql.database.azure.com",
"sourceServerId": "",
"publicNetworkAccess": "Disabled",
"sslEnforcement": "Disabled",
"haEnabled": "Disabled",
"earliestRestoreDate": "2020-12-17T18:49:40.7766824+08:00",
"replicationRole": "None",
"replicaCapacity": 10,
"delegatedSubnetArguments": {
"subnetArmResourceId": "/subscriptions/9e223dbe-3399-4e19-88eb-0975f02ac87f/resourceGroups/yemingtemp/providers/Microsoft.Network/virtualNetworks/VNETmysql-test-100/subnets/Subnetmysql-test-100"
},
"byokEnforcement": "Disabled"
},
"location": "West US 2",
"id": "/subscriptions/9e223dbe-3399-4e19-88eb-0975f02ac87f/resourceGroups/yemingtemp/providers/Microsoft.DBforMySQL/flexibleServers/mysql-test-100",
"name": "mysql-test-100",
"type": "Microsoft.DBforMySQL/flexibleServers"
}
]
}
```

The PosrgreSql have the same issue.
## Cost