xSQLServerAlwaysOnAvailabilityGroup: Should Be Cluster Aware

[randomnote1]

Details of the scenario you tried and the problem that is occurring:
When the xSQLServerAlwaysOnAvailabilityGroup resource is applied to all of the nodes in a Failover Cluster Instance (FCI), the nodes will "fight" with each other while trying to create and configure the availability group.

The DSC configuration that is using the resource (as detailed as possible):
The following configuration applied to two or more nodes that host the FCI:

xSQLServerAlwaysOnAvailabilityGroup AddTestAG
{
    Ensure               = 'Present'
    Name                 = 'TestAG'
    SQLInstanceName      = $Node.SQLInstanceName
    SQLServer            = $Node.NodeName
    DependsOn            = '[xSQLServerEndpoint]HADREndpoint', '[xSQLServerPermission]AddNTServiceClusSvcPermissions'
    PsDscRunAsCredential = $SysAdminAccount
}

Version of the Operating System, SQL Server and PowerShell the DSC Target Node is running:
Any

What module (SqlServer or SQLPS) and which version of the module the DSC Target Node is running:
Any

Version of the DSC module you're using, or 'dev' if you're using current dev branch:
Any

[randomnote1]

The resource should evaluate if the current node is actively hosting the SQL instance. If it is not hosting the instance, it should write a verbose message stating that it does not own the instance, and then silently exit.

[randomnote1]

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