[tsp-client convert] ARM converter adds @useAuth to main.tsp

[darkoa-msft]

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tsp-client convert --arm adds @useAuth(AadOauth2Auth<["user_impersonation"]>) to main.tsp, which causes the wrong security definition to be created in ARM swagger.

Expected behavior After conversion, running tsp compile should produce the standard security definition.

Additional context To repro, take an existing swagger, convert it and check main.tsp