feat(AIP-133): ignore create methods with invalid LRO response types

[andrei-scripniciuc]

This addresses a nil dereferencing error due to ot being nil in https://github.com/andrei-scripniciuc/api-linter/blob/f6108f07532aae07c4f305c7da99092f0114cea2/rules/aip0133/request_required_fields.go#L50