Microsoft.Network/p2svpnGateways Ability to set configurationPolicyGroupAssociations

### Resource Type

Microsoft.Network/p2svpnGateways

### Api Version

2024-03-01

### Issue Type

Property(s) inaccurately marked read-only/write-only

### Other Notes

I have found no way of associating a configurationPolicyGroup with a p2SConnectionConfigurations because the configurationPolicyGroupAssociations is marked as read-only. The only way around this i have found is to suppress the warning

### Bicep Repro

```
var test = vpnServerConfig.properties.configurationPolicyGroups[0].id
var test2 = vpnServerConfig.properties.configurationPolicyGroups[1].id

resource vpnGateway 'Microsoft.Network/p2svpnGateways@2024-03-01' = {
name: 'p2s-${resourceSuffix}'
location: location
properties: {
virtualHub: {
id: hubId
}
p2SConnectionConfigurations: [
{
id: test
name: 'P2SConfig'
properties: {
vpnClientAddressPool: {
addressPrefixes: [
'10.16.0.0/28'
]
}
configurationPolicyGroupAssociations: [{
id: test
}
{
id: test2
}]
}
}
]
vpnGatewayScaleUnit: 1
vpnServerConfiguration: {
id: vpnServerConfig.id
}
}
}
```

### Confirm

- [x] I have read the troubleshooting guide and looked for duplicates.

Use the Microsoft.Network/p2svpnGateways@2024-03-01 resource definition as the entry point, focusing on p2SConnectionConfigurations.configurationPolicyGroupAssociations. Compare its declared mutability with the Bicep repro, then verify that associations can be specified without a read-only warning; the issue mentions no file or test to run.

Written by the indexing model from the issue text.