General Purpose SKU deployment fails

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[101-sql-elastic-pool-create](https://raw.githubusercontent.com/Azure/azure-quickstart-templates/master/101-sql-elastic-pool-create/azuredeploy.json)

### Issue Details
Deploying the general purpose elasticpool edition throws this error {"code":"DeploymentFailed","message":"At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/DeployOperations for usage details.","details":[{"code":"InvalidTierSkuCombination","message":"The tier 'GeneralPurpose' does not support the sku 'SQLDB_GP_Gen5'."}]}

### Repro steps (*if necessary, delete otherwise*)
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Start with 101-sql-elastic-pool-create/azuredeploy.json, linked in the issue, and inspect the elastic pool tier and SKU settings. Reproduce the deployment and verify the template uses a supported GeneralPurpose SKU combination so the deployment completes without InvalidTierSkuCombination.

Written by the indexing model from the issue text.