Function to obtain the paired/failover region

As a user, I would like the ability to pick the zone related to the redunacy. It's better to explain it by example. Imagine the following Bicep file:

```bicep
module cosmosDb 'br/public:avm/res/document-db/database-account:0.10.1' = {
name: 'cosmosDb'
params: {
name: cosmosDbName
location: 'westus'
disableLocalAuth: true
networkRestrictions: {
publicNetworkAccess: 'Enabled'
networkAclBypass: 'AzureServices'
ipRules: [
'13.91.105.215'
'4.210.172.107'
'13.88.56.148'
'40.91.218.243'
'0.0.0.0'
]
}
locations: [
{
failoverPriority: 0
locationName: 'West US'
isZoneRedundant: false
}
{
failoverPriority: 1
locationName: 'Central US'
isZoneRedundant: false
}
]
enableFreeTier: false
databaseAccountOfferType: 'Standard'
backupPolicyType: 'Periodic'
backupIntervalInMinutes: 240
backupRetentionIntervalInHours: 720
backupStorageRedundancy: 'Geo'
defaultConsistencyLevel: 'Session'
maxStalenessPrefix: 100
maxIntervalInSeconds: 5
sqlDatabases: [
{
name: 'test'
}
]
}
]
}
}
```

The location parameter can be set, which takes me to the locations parameter. For the failover priority, I can use: `pickZones('Microsoft.DocumentDB', 'databaseAccounts', location)`. The challenge is in the second part. It would be beneficial if there were a function like: `pickZoneReferenceName('Microsoft.DocumentDB', 'databaseAccounts', location)`.

If this issue has already been captured or if such a function exists, I hope you can steer me in the right direction.

The issue names no repository files or tests. Start by reviewing the existing pickZones('Microsoft.DocumentDB', 'databaseAccounts', location) function and the Bicep example, then determine how a paired or failover region reference name should be selected; done means the requested function behavior is defined and validated for the shown Cosmos DB scenario.

Written by the indexing model from the issue text.