Optional parameters aren't really optional for create

--end-ip-address and --start-ip-address are listed as optional, but I've never seen it work without them.

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* ID: a0ed8c3b-f42d-2421-a563-d09ec7b67ac0
* Version Independent ID: bcdaeb1b-e343-2336-d394-e32f8d867ab2
* Content: [az sql server firewall-rule](https://docs.microsoft.com/en-us/cli/azure/sql/server/firewall-rule?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/sql/server/firewall-rule.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/main/latest/docs-ref-autogen/sql/server/firewall-rule.yml)
* Service: **sql-database**
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* Microsoft Alias: **routlaw**