`@azure-tools/typespec-azure-resource-manager/no-resource-delete-operation` rule shouldn't complain for singleton resources

[Playground](https://azure.github.io/typespec-azure/playground?c=aW1wb3J0ICJAdHlwZXNwZWMvcmVzdCI7CtIZdmVyc2lvbmluZ8wfYXp1cmUtdG9vbHMvyCstxhVjb3Jl3yvIK3Jlc291cmNlLW1hbmFnZXIiOwoKdXNpbmcgVHlwZVNwZWMuSHR0cDvQFVJlc3TRFVbpAKnIG0HEZS5Db3JlzhJSx3dNxnY7CgovKiogQ29udG9zbyDIHiBQcm92aWRlciDmAJ5tZW50IEFQSS4gKi8KQGFybcggTmFtZXNwYWNlCkBzZXJ2aWNlKHsKICB0aXRsZTogIsdYyC5IdWJDbGllbnQiLAp9KQpA5wFgZWQo5wDBcykKbshSIE1pY3Jvc29mdC7SR%2B8AuEFQSSDHTXPkAKNlbnVtIMhUIOQAksQuMjAyMS0xMC0wMS1wcmV2aWV3yDXENCAgQHVzZURlcGVuZGVuY3ko9QEx6AFrcy52MV8wX1DGSF8xKcRAYXJtQ29tbW9u5AGZc8cq10jLKctUNcRIYPIAqWAsCn3mAPNB6AD16wEOIOgCTeUBn%2BQB7mxldG9uKCJkZWZhdWx0IikKbW9kZWwgRW1wbG95ZWUgaXMgVHJhY2tlZOgAmDzIHFByb3BlcnRpZXM%2B5QE6Li7pALzkAe5QYXJhbWV0ZXLJMT476ACcyV9wyUTkAJLOfMpg6QGZQWdlIG9mIGXIP%2BUBjmFnZT86IGludDMyOwrHKUNpdHnSKmNpdHk%2FOiBzdHLlAwHHLFByb2ZpbNNZQGVuY29kZSgiYmFzZTY0dXJsIuQBdnDGMD86IGJ5dGVzyUhUaGUgc3RhdHVzxEt0aGUgbGFzdCDkAMVhdGlvbuUDFCAgQHZpc2liaWxpdHkoInJlYWTIVcQY5QObU3RhdMRf5QG5zBTpAUDEa8wyxXjlAMJh6QHjxW9AbHJvxDt1cwp1buQCwNFU5QFc6AG40R4s7ADdyFrkAhViZcR36QCEZWTEbiDNXzogIswPItlMdXBkYXTET8VDVccOOiAiyAvaO%2BYAh2RlbGV06ACDRMQNxkDIC9dAY3Jl5AEBcmVxdWVzdCBoYcRQZW4gYWNjZXDJUEHHDjogIsgLxlDmAkflA3BpbnRlcmbkBIxP6AHucyBleHRlbmRz9gVQLsspe30KCiNzdXBwcmVzc%2F8GDe8GDS9ub8oU5gEHLekCcSIgIlNpbmdlbHRvbukA9iLlBZfoAI7qAIbrAMToA4HmA3hnZXTkAWpByjVSZWFk7APVIOcBSk9y5QGx5QGZyy9Dxx1SZXBsYWNlQXN5bmPOP%2BUCAdA3UGF0Y2hTzCws8wQbxUBsaXPwAKRMaXN0QnlQYXJlbnTObeYFHHNhbXBs6wIMYWPkAQYgdGhhdCBtb3Zl6gQLdG8gZGlmZmXESiBsb2PlAS%2FmAhvFKc54QcVI7wC3TW92ZVLmAmbIDXNwb25z5ACR8ACSSEVBROoENMR%2BY2hlY2vqAKpleGlzdGVu5gXEIMYeRckU7wF7zR38BYnlAMvoAwrpBYvrALnpBYTkA0Ntb3bkA3hmcm9t7wETxBPxBWLLM3RvzzF0b8ov9wCV5gEs8ACWxxbsAJfuBX7FPugBqOcE0XVzzG4%3D&e=%40azure-tools%2Ftypespec-autorest&options=%7B%7D)

Doesn't make sense to have delete for the singleton resource so rule could be smarter

Start with the linked Playground example and locate the implementation of the @azure-tools/typespec-azure-resource-manager/no-resource-delete-operation rule. Confirm how the rule identifies singleton resources, then inspect nearby rule tests or test conventions. Done means singleton resources no longer trigger this diagnostic while ordinary resources retain the existing check.

Written by the indexing model from the issue text.